Preparation and Performances Study of Nano-ZnO/Graphene Potassium Silicate Zinc-rich Coatings

Preparation and Performances Study of Nano-ZnO/Graphene Potassium Silicate Zinc-rich Coatings | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Preparation and Performances Study of Nano-ZnO/Graphene Potassium Silicate Zinc-rich Coatings qingbo lyu, feiyu guo, ziming huang, yunshan bai, huanhuan liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4209341/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 20 Aug, 2024 Read the published version in Chemical Papers → Version 1 posted 5 You are reading this latest preprint version Abstract Nano-ZnO/graphene composites were prepared and added to potassium silicate zinc-rich coatings in order to obtain Nano-ZnO/graphene potassium silicate zinc-rich anti-corrosion coatings. Their morphology and corrosion resistance were charactered by scanning electron microscopy, electrochemical testing, and salt spray testing. The effect of Nano-ZnO/grapheme contents on the anticorrosion performance of coatings was also studied. Compared to neat water-based potassium silicate zinc-rich coatings with 50wt% zinc, Nano-ZnO/graphene potassium silicate zinc-rich coating with 30wt% zinc and 1wt% Nano-ZnO/graphene has better corrosion resistance. Their water resistance and E corr are improved, i corr is reduced by one order of magnitude, | Z | 0.01Hz is increased by six times, and R ct is increased by three times. This study indicates that Nano-ZnO/graphene not only enhances anti-corrosion performance of potassium silicate zinc-rich anti-corrosion coatings, but also improves the utilization rate of zinc powder. Potassium silicate zinc-rich coating Graphene Nano-ZnO Corrosion resistance Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Introduction Corrosion is the phenomenon which metal is destroyed by the interaction between metal and its environment in which it is located.(Q. H. Wang et al. 2023 ) According to relevant research reports, corrosion is becoming increasingly serious.(Vanaei, Eslami, and Egbewande 2017 ) The economic and environmental problems caused by corrosion urgently need to be addressed. Coating protection is currently one of the most widely used and cost-effective anti-corrosion methods.(Wen Sun et al. 2021) Oil-based anti-corrosion coatings contain a large amount of volatile organic compounds (VOCs) that can cause significant harm to the environment and human body, (Wei, Cheng, and Li 2014 ; H. Wang et al. 2013 ) while water-based inorganic zinc-rich coatings have the advantages of low VOCs emissions and easy cleaning after construction, which are deeply loved by people. (Liu, Zhan, and Li 2012 ) Water-based potassium silicate zinc-rich anti-corrosion coating is one of them, but it has disadvantages such as poor water resistance, high zinc content which easily damage to the health of construction personnel. Therefore, it is necessary to improve the corrosion resistance of potassium silicate zinc-rich anti-corrosion coatings and reduce zinc content. Graphene has good mechanical stability, low chemical reactivity, gas impermeability, and good barrier property(Wei, Cheng, and Li 2014 ; H. Wang et al. 2013 ; Wen Sun et al. 2021). It can be applied in anti-corrosion coatings. Cheng et al.(Cheng et al. 2019 ) prepared graphene/water-based potassium silicate zinc-rich coatings and studied the effect of graphene content on various performances of the coatings. The results indicated that water-based potassium silicate coating containing 2wt% graphene and 80wt% zinc particles can provide 40 days of cathodic protection for carbon steel substrates. However, its zinc content is still very high. This is because graphene has not fully utilized its excellent properties. It has a large specific surface area. (Chae, Siberio-Pérez, and Kim 2004 ) There are van der Waals forces and π - π bonds between the layers, making it easy to agglomerate and poor to disperse in coatings. (Yuan 2011 ; Ollik and Lieder 2020 ) Therefore, researchers often modify graphene to improve its anti-corrosion performance. Cai et al.(Cai, Zuo, and Luo 2016 ) prepared polyaniline/graphene composites by in-situ polymerization, and uniformly dispersed them in water-borne polyurethane coatings. The results showed that the performance of coating which contained 0.75wt% polyaniline/graphene composite was better than that of 4wt% graphene. Xiao et al.(F. J. Xiao et al. 2018 ) prepared polyaniline/graphite oxide composite and doped it into water-borne epoxy acrylate zinc-rich coating to prepare polyaniline/graphite oxide water-borne epoxy acrylate zinc-rich coating. Research has shown that its corrosion resistance was better than that of coatings which was undoped. Nano-ZnO is known as a multifunctional material due to its unique physical and chemical properties, which has advantages such as good photocatalytic activity, high stability, environmental friendliness, and low price.(Rokhsat and Akhavan 2016 ; M. Xiao, Lu, and Li 2014 ; B and W 2012; Zhang, Huang, and Du 2020 ) At present, there are few reports on the impact of Nano-ZnO/graphene composites on the anti-corrosion performance of water-based potassium silicate zinc-rich coatings. In this paper, graphene was prepared by chemical vapor deposition (CVD). Its surface was modified by Nano-ZnO in order to improve its dispersability in coatings and give full play to its excellent anti-corrosion performance. Nano-ZnO/graphene (Nano-ZnO/Gr) was added to potassium silicate zinc-rich coatings to prepare coatings with low zinc content and high corrosion resistance. This can provide a method for upgrading the anti-corrosion performance of potassium silicate zinc-rich coatings. Experimental Materials MgO is analytically pure and prepared according to a reference. (Bai, Liu, and Liu 2005) Nitrogen and methane are purchased from Xi'an Longteng Chemical Co., Ltd. Zinc powder, zinc acetate, ethanol, hydrochloric acid, and sodium hydroxide are analytical reagents and purchased from China National Pharmaceutical Group Chemical Reagent Co., Ltd. Potassium silicate and alkaline silica sol are industrial grade and purchased from Guangzhou Yixin Chemical Co., Ltd. The silane coupling agent KH560 is industrial grade and purchased from Dinghai Plastic Chemical Co., Ltd. Dispersant 5040, defoamer EFKA2722, thickener, and leveling agent EFKA3777 are industrial grade and purchased from Shandong Yousuo Chemical Co., Ltd. Steel substrate are Q235 cold-rolled steel plate: 90 mm × 50 mm × 2 mm, purchased from Shenzhen Hongwang Mould Co., Ltd. Method Preparation of Graphene Initially, magnesium oxide with a spherical morphology was extracted from dolomite ore by the Ammonium salt extracting method(Bai, Liu, and Liu 2005). The quartz boat which contained 4.0 g MgO was placed in a tube furnace which was filled with nitrogen gas. When the temperature raised to 950 °C, methane was injected to the tube furnace at a flow rate of 1.5 L/min. The reaction was carried out at a constant temperature of 950 °C for 20 min. Then, the tube furnace cooled to room temperature. Nitrogen and methane were stopped injecting. The sample was take out from the tube furnace. 250 mL 4.0 mol/L hydrochloric acid solution was added to the sample. The mixture was stirred for 3 h and then washed with deionized water until there was no Cl-. It was dried in a oven at 60 °C for 24 h to obtain graphene (Gr). Preparation of Nano-ZnO/Gr Composite 30 mL10% zinc acetate solution and 5 mL 0.4 g/mL graphene ethanol dispersion were mixed and stirred for 30 min. Its pH was adjusted to 11 with NaOH solution and then stirred for 2 h. The mixture was poured into a reactor and reacted in a oven at 120℃ for 18 h. Then it was washed with deionized water and ethanol, respectively, and dried for 2 h at 80 ℃. Nano-ZnO/Graphene composite was obtained which was a black powder. Preparation of Nano-ZnO/Gr Potassium Silicate Zinc-rich Coating Potassium silicate solution and alkaline silica sol solution were mixed in a 1:1 mass ratio, stirred at 45 ℃ for 2 h, and standed at room temperature to prepare potassium silicate base material with a modulus of 5.5. 3.0 g potassium silicate base material, 0.1 g thickener, 0.1 g leveling agent, 0.1 g defoamer, 0.1 g dispersant, and 0.2 g KH560 were added to 2.4 g deionized water. The mixture was stirred for 30 min to prepare component A. Different weights of Nano-ZnO/Gr (B component, wt.% of total component content: 0, 0.5, 1, 1.5, 2) and different amounts of zinc powder (C component, wt.% of total component content: 20, 30, 40, 50, 60, 70) were added to the component and stirred for 60 min to prepare a series of water-based potassium silicate zinc-rich coatings which contained different contents of Nano-ZnO/Gr and zinc powder. Nano-ZnO/Gr water-based potassium silicate zinc-rich coatings were uniformly applied on pretreated (polished, degreased) steel plate specimens by an automatic coating machine (thickness controlled at 90 ±5μm). Then, it stood at room temperature for more than 24 h to obtain Nano-ZnO/Gr potassium silicate zinc-rich coatings. Main Instruments AFA-III automatic film applicator was used to prepare potassium silicate zinc-rich coatings at. Byes-60B precision brine spray testing machine was employed to test corrosion resistance with the ISO 9227:2017 standard. QFH-A pencil hardness tester was used to character hardness of coatings with ISO 15184:2020 standard. QFH-A baige knife was used to conduct grid cutting tests on the coating surface to measure the adhesion of the coating with ISO 2409:2020 standard.Quanta 200 scanning electron microscope and FEI-Tecnai G2 F20 Field emission transmission electron microscope were used to analysis the morphology of Nano-ZnO/grapheme. Tensor 27 infrared spectrometer was used to character the infrared spectra of graphene, Nano-ZnO, and Nano-ZnO/Gr. The Contact Angle System with high-speed camera determined the contact angle of coating surfaces. An electrochemical analyser (CHI660D) was used to measure the corrosion in 3.5% NaCl simulated seawater conditions. Three-point electrodes, which are the working electrode (coated steel plates), reference electrode (Ag/AgCl 2 ), and counter electrode (platinum) were used for the corrosion test. Electrochemical impedance spectroscopy (EIS) was performed over a frequency range of 10 5 to 10 -2 Hz, while the dynamic potential polarization curve assessments were obtained at a scan rate of 1 mV/s, within a potential window of ±300 mV relative to the open circuit potential. Results and discussion Structural Characterization of Gr and Nano-ZnO/Gr Characterization of graphene, as depicted in Fig. 1 , reveals a layered morphology in scanning electron microscopy (SEM) images, with graphene sheets (Gr) exhibiting a loosely stacked arrangement devoid of significant overlap (Fig. 1 (a)). Transmission electron microscopy (TEM) further elucidates that these layers are composed of interwoven 50 nm independent microspheres(Fig. 1 (b)). Subsequent Brunauer-Emmett-Teller (BET) surface area and porosity analysis delineate a typical Type IV nitrogen adsorption-desorption isotherm, indicative of a mesoporous structure ((Fig. 1 (c)). Analysis infers the presence of approximately 1 nm micropores within the smallest microsphere units, yielding a surface area of 312.12 m 2 /g and an average pore size of 30.79 nm((Fig. 1 (d)). Figure 2 (a) presents the SEM image of Nano-ZnO/Gr composite. Graphene appears in a sheet-like form. Granular nano ZnO particles are uniformly dispersed on the surface of graphene. Figure 2 (b) showed the infrared spectra of graphene, Nano-ZnO, and Nano-ZnO/Gr. Nano-ZnO exhibited a strong absorption peak at 453 cm -1 , which was an asymmetric stretching vibration peak of the Zn-O bond. The absorption peak of graphene at 1640 cm -1 was the stretching vibration peak of the C = C double bond. The absorption peak at 1053 cm -1 was the stretching vibration peak of the C = O double bond. The absorption peak at 3462 cm -1 was the stretching vibration peak of the -O-H bond, indicating the presence of oxygen-containing functional groups on the graphene. The infrared spectrum of Nano-ZnO/Gr showed characteristic absorption peaks of Nano-ZnO and graphene. The shape of the absorption peak at 453 cm -1 became wide. Meanwhile, the intensity of the absorption peak at 3462 cm -1 weakened. These indicated that there was the interaction between Nano-ZnO and graphene. Therefore, the Nano-ZnO/Gr composite was formed. Performances of Nano-ZnO/Gr Potassium Silicate Zinc-rich Coatings Coating Adhesion Test Figure 3 showed the adhesion test diagram of coatings containing zinc and Nano-ZnO/Gr with different mass fractions. When the Zn and Nano-ZnO/Gr content were 30wt% and less than or equal 1.5wt%, respectively, the adhesion of the coatings were optimal because graphene acted as adhesion promoters for the steel substrate, resulted in firmly binding to the substrate with coating(S. G. Wang et al. 2019 ). When the content of Nano-ZnO/Gr was too high, its dispersibility in the potassium silicate matrix was poor, which easily leaded to Nano-ZnO/Gr aggregate. When the zinc content was greater than 60wt%, the coating which contained Nano-ZnO/Gr did not meet the standard of the adhesion. Therefore, the performances of coatings with 60wt% and 70wt% zinc content would no longer be studied. Coating hardness test Figure 4 showed the hardness test results of coatings with different content of zinc powder and Nano-ZnO/Gr. It can be seen that when the zinc content and Nano ZnO/Gr content were 30wt% and 1wt%, respectively, the hardness of the coating reached the maximum hardness grade up to 4H. This was because both zinc powder and ZnO of the Nano-ZnO/Gr composite reacted with Si-O bonds. Meanwhile, the Nano-ZnO/Gr composite was used as filler to fill micropores and flaws of the coatings. (W. Sun et al. 2014 ) Therefore, the coating with high density and hardness was formed. Contact angle testing of coating surfaces Figure 5 showed the contact angle test of coatings with Nano-ZnO/Gr. It can be seen that as the content of Nano-ZnO/Gr increased, the contact angle of coatings with different zinc contents first increased and then decreased. When the coating contained 30wt% zinc and 1wt% Nano-ZnO/Gr, its contact angle increased from 42° to 75.8°, indicating excellent hydrophobicity. This can be attributed to the good dispersibility of Nano-ZnO/Gr in silicate matrix which can make the coating surface smoother and more uniform. Coating corrosion resistance test Figure 6 showed the water resistance test diagram of coatings with Nano-ZnO/Gr. It can be seen that the coating with 30wt% zinc and 1wt% Nano-ZnO/Gr exhibited the best water resistance. This was because the zinc powder and Nano-ZnO/Gr in the coating were fully mixed with the potassium silicate matrix to form a dense coating. Furthermore, the Nano-ZnO/Gr flakes formed a tortuous diffusion pathway, which prevent water from reaching the substrate surface. Electrochemical analysis of coatings Figure 7 showed the potentiodynamic polarization curves of coatings with Nano-ZnO/Gr soaked in 3.5% NaCl solution for 12 h. Table 1 showed the parameters obtained from the corresponding potentiodynamic polarization curves in Fig. 7 . It can be seen that the E corr of the steel plate sample coated with Nano-ZnO/Gr potassium silicate zinc-rich coating significantly increases, while the i corr substantially decreased, indicating that the coating with Nano-ZnO/Gr had good anticorrosion resistance. From the data in the Table 1 , it can be seen that when the coating contained 30wt% zinc and 1wt% Nano-ZnO/Gr, its i corr was the smallest, decreasing to 7.82×10 − 7 A/cm 2 , with a larger E corr of -0.589 V, indicating the coating had the best corrosion resistance among them. Zinc oxide on graphene sheets can reduce graphene clusters. At the same time, it has a certain polarity and can interact with the substrate, making graphene more evenly dispersed in aqueous potassium silicate coatings. This fully utilizes the barrier effect and conductivity of graphene, thereby improving the utilization efficiency of zinc powder. When the content of Nano-ZnO/Gr exceeded 1%, graphene would aggregate which can reduce its anti-corrosion performance. Table 1 The parameters obtained from polarization curves of coatings with different zinc content and Nano-ZnO/Gr content Zinc(wt%) Nano-ZnO/Gr(wt%) E corr (V) i corr (A/cm 2 ) Bare steel - -0.82 3.33×10 − 4 20 0.0 -0.68 6.45×10 − 5 0.5 -0.58 7.31×10 − 6 1.0 -0.60 9.07×10 − 6 1.5 -0.67 1.07×10 − 5 2.0 -0.67 1.81×10 − 5 30 0.0 -0.69 1.11×10 − 5 0.5 -0.63 1.54×10 − 6 1.0 -0.59 7.80×10 − 7 1.5 -0.68 1.87×10 − 6 2.0 -0.68 2.42×10 − 6 40 0.0 -0.66 1.25×10 − 5 0.5 -0.59 5.39×10 − 6 1.0 -0.58 1.86×10 − 5 1.5 -0.71 3.60×10 − 5 2.0 -0.66 5.22×10 − 5 50 0.0 -0.63 8.63×10 − 6 0.5 -0.60 2.59×10 − 6 1.0 -0.62 3.48×10 − 6 1.5 -0.72 9.05×10 − 6 2.0 -0.77 2.11×10 − 5 Figure 8 illustrates the impedance spectra of coatings with Nano-ZnO/graphene composite which were immersed in 3.5% NaCl solution for 24 h, including Bode and Nyquist plots. Figure 9 showed the impedance mode values (| Z | 0.01Hz ) of the coating at 0.01 Hz obtained from the Bode plot. Figure 10 showed the coating charge transfer resistance ( R ct ) data obtained from the Nyquist plot. It can be seen that the coating with 30wt% zinc and 1wt% Nano-ZnO/Gr content of had the maximum | Z | 0.01Hz and R ct , reaching 3.069×10 4 Ω·cm2 and 3.045×10 4 Ω·cm 2 , respectively. This was consistent with the previous physical performances and electrochemical testing of the coatings. Conclusions Nano-ZnO/Gr composites were prepared by hydrothermal synthesis method and studied their effect on the anti-corrosion performances of potassium silicate zinc-rich coatings. When the zinc power and Nano-ZnO/Gr content were 30wt% and 1wt%, respectively, the potassium silicate zinc-rich coating exhibited the excellent anti-corrosion performance with adhesion of grade 1, hardness of 4H, E corr of -0.589 V, i corr of 7.82×10 − 7 A/cm 2 , | Z | 0.01Hz of 2.62×10 4 Ω·cm 2 , R ct of 2.91×10 4 Ω·cm 2 . Compared with the neat coating, the physical and electrochemical properties of potassium silicate zinc-rich coating containing Nano-ZnO/Gr were significantly polished, exhibiting long-term corrosion resistance. Furthermore, its zinc content was greatly reduced. This study indicated that doping appropriate amount of Nano-ZnO/Gr composites into potassium silicate zinc rich coatings can effectively enhance the excellent anti-corrosion performance of graphene in coatings and the utilization rate of zinc powder due to tortious diffusion pathways and a better electrical connection between zinc particles and steel substrate. This method is a simple and efficient way to improve the anti-corrosion performance of water-based potassium silicate zinc-rich coatings. Declarations Author contributions: They contribute 100% to the study work's development, from experimentation to analysis. Funding: There is no money available for this project. Availability of data and materials: The authors confirm that the data supporting this study's conclusions is included in the publication. Conflict of interest: There are no conflicting interests to disclose in this study. Acceptance of ethics: Because this experiment does not involve people or animals, no ethics committee approval is required. Consent of participants: Because this study does not include people or animals, no permission is required to participate. Publishing permission: The writers grant their permission for the work to be published by the publisher. Consent to publish: The authors give the publisher the consent to publish the work. Acknowledgments. This research received no external funding. References B, Kumar, and Kim S. W. 2012. “Energy Harvesting Based on Semiconducting Piezoelectric ZnO Nanostructures.” Nano Energy 1 (3): 342–55. https://doi.org/10.1016/j.nanoen.2012.02.001. 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Cite Share Download PDF Status: Published Journal Publication published 20 Aug, 2024 Read the published version in Chemical Papers → Version 1 posted Reviewers agreed at journal 10 Apr, 2024 Reviewers invited by journal 05 Apr, 2024 Editor invited by journal 04 Apr, 2024 Editor assigned by journal 04 Apr, 2024 First submitted to journal 02 Apr, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4209341","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":287794116,"identity":"010aa7e6-680a-4ae6-9a85-ee23da1838c3","order_by":0,"name":"qingbo lyu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAw0lEQVRIiWNgGAWjYBACAxDxgMEGymUjVksCQxrpWg6ToMWcvfmZRGLbeXtz6R4Dhg9lhxn4Zzfg12LZc8wMqOV24s45ZwwYZ5w7zCBx5wABh91IMJNIOHM7weBGjgEzb9thBgOJBAJa7j//BtRyzh6s5S9RWm7wAG2pOMC4AaSFkRgtlj05xRYJFcmJG26kFRzsOZfOI3GDgBZz9uMbb3wwsAM6LHnjgx9l1nL8MwhoQQEHgJiHBPWjYBSMglEwCnABADPWQwVB64ohAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0009-0003-9487-3995","institution":"shaanxi shifan daxue: Shaanxi Normal University","correspondingAuthor":true,"prefix":"","firstName":"qingbo","middleName":"","lastName":"lyu","suffix":""},{"id":287794117,"identity":"e6a70c53-3778-404e-8d6b-99b58ca2ccd9","order_by":1,"name":"feiyu guo","email":"","orcid":"","institution":"shaanxi shifan daxue: Shaanxi Normal University","correspondingAuthor":false,"prefix":"","firstName":"feiyu","middleName":"","lastName":"guo","suffix":""},{"id":287794118,"identity":"c6574d3a-8ecc-4c94-8a28-f05a397398f6","order_by":2,"name":"ziming huang","email":"","orcid":"","institution":"shaanxi shifan daxue: Shaanxi Normal University","correspondingAuthor":false,"prefix":"","firstName":"ziming","middleName":"","lastName":"huang","suffix":""},{"id":287794119,"identity":"52e25849-14c5-4491-b3fd-f33de733af24","order_by":3,"name":"yunshan bai","email":"","orcid":"","institution":"shaanxi shifan daxue: Shaanxi Normal University","correspondingAuthor":false,"prefix":"","firstName":"yunshan","middleName":"","lastName":"bai","suffix":""},{"id":287794120,"identity":"dc9f153f-3be6-4706-a4d6-f8aa53876ed0","order_by":4,"name":"huanhuan liu","email":"","orcid":"https://orcid.org/0000-0002-7196-4013","institution":"shaanxi shifan daxue: Shaanxi Normal University","correspondingAuthor":false,"prefix":"","firstName":"huanhuan","middleName":"","lastName":"liu","suffix":""}],"badges":[],"createdAt":"2024-04-03 02:08:57","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4209341/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4209341/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11696-024-03645-6","type":"published","date":"2024-08-20T15:57:53+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":54354841,"identity":"0b6af9d9-3915-4c89-8313-72584e2e40d2","added_by":"auto","created_at":"2024-04-09 09:31:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":651033,"visible":true,"origin":"","legend":"\u003cp\u003eCharacterization on the Gr.\u003cstrong\u003e \u003c/strong\u003e(a) SEM of Gr; (b) TEM of Gr; (c) N\u003csub\u003e2\u003c/sub\u003e isotherms of Gr; (d) pore size distributions derived from isothermal adsorption plots of Gr.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/c6a11958dc25bbf0d563d37d.png"},{"id":54354842,"identity":"8721a49e-6031-46ec-bce3-48f264f10ba3","added_by":"auto","created_at":"2024-04-09 09:31:52","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":162004,"visible":true,"origin":"","legend":"\u003cp\u003e(a) SEM of Nano-ZnO/Gr; (b) Infrared spectra of graphene, Nano-ZnO, and Nano-ZnO/Gr.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/5a3b8f1902e8733c1c894371.png"},{"id":54354840,"identity":"f754dab3-04f0-4456-aeca-eee028742f81","added_by":"auto","created_at":"2024-04-09 09:31:52","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":235900,"visible":true,"origin":"","legend":"\u003cp\u003eAdhesion of coatings containing different content of Zinc powder and Nano-ZnO/Gr (Cp represents Nano-ZnO/Gr).\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/2eac7c403da1edcc11dcdc49.png"},{"id":54354837,"identity":"7f9dc3a2-a60f-4cf6-9563-91c10c2e29fb","added_by":"auto","created_at":"2024-04-09 09:31:51","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":112603,"visible":true,"origin":"","legend":"\u003cp\u003eHardness testing of coatings with different content of Zn and Nano-ZnO/Gr. (Cp represents Nano-ZnO/Gr)\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/836eecdff831254f05c06732.png"},{"id":54354849,"identity":"c5aed749-b595-462d-b0af-51a5d5495881","added_by":"auto","created_at":"2024-04-09 09:31:53","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":60179,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurement of contact angle of coatings with different content of Zn and Nano-ZnO/Gr\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/c15037383c8fecab21f42767.png"},{"id":54354838,"identity":"ac072539-f50f-4633-9cbb-158983dd36ec","added_by":"auto","created_at":"2024-04-09 09:31:51","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":130977,"visible":true,"origin":"","legend":"\u003cp\u003eWater resistance testing of coatings with different content of Zn and Nano-ZnO/Gr\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/a075a362e6b41573e0349b7d.png"},{"id":54354846,"identity":"db045403-cbee-47ec-a21b-6b884d97e166","added_by":"auto","created_at":"2024-04-09 09:31:53","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":101118,"visible":true,"origin":"","legend":"\u003cp\u003ePotentiodynamic polarization curves of coatings with different content of Zn and Nano-ZnO/Gr. (a) 20wt% Zn; (b) 30wt% Zn; (c) 40wt% Zn; (d) 50wt% Zn\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/46de34e80cfa1cc5d5c0fc96.png"},{"id":54354845,"identity":"225f388f-c9d6-4d82-82cc-6725b46d843e","added_by":"auto","created_at":"2024-04-09 09:31:53","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":303987,"visible":true,"origin":"","legend":"\u003cp\u003eBode and Nyquist plots of coatings with different content of Zn and Nano-ZnO/Gr soaked in 3.5% NaCl solution for 24 h. (a) and (a') 20wt% Zn; (b) and (b') 30wt% Zn; (c) And (c') 40wt% Zn; (d) and (d') 50wt% Zn\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/fa1edd801f0a7bac52668ce3.png"},{"id":54354836,"identity":"9bd83dd1-3620-4109-b9bb-638401a14501","added_by":"auto","created_at":"2024-04-09 09:31:51","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":46608,"visible":true,"origin":"","legend":"\u003cp\u003eFitting impedance modal values of coatings with different content of Zn and Nano-ZnO/Gr at 0.01 Hz (|\u003cem\u003eZ\u003c/em\u003e|0.01Hz)\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/22c47ceac4d925c945692dbc.png"},{"id":54354850,"identity":"ddbba5f7-d003-4345-a4c4-2cbf3f92af30","added_by":"auto","created_at":"2024-04-09 09:31:53","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":73392,"visible":true,"origin":"","legend":"\u003cp\u003eFitting charge transfer resistance (\u003cem\u003eR\u003c/em\u003e\u003csub\u003ect\u003c/sub\u003e) of coatings with different content of Zn and Nano-ZnO/Gr\u003c/p\u003e","description":"","filename":"floatimage10.png","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/4419e21182dcdc99525ebd9c.png"},{"id":63998549,"identity":"0e188868-e48a-45d5-8da7-c94bc2353878","added_by":"auto","created_at":"2024-09-04 18:20:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2401402,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4209341/v1/6c0bdcbd-a700-4830-80af-a24c1ed039b4.pdf"}],"financialInterests":"","formattedTitle":"Preparation and Performances Study of Nano-ZnO/Graphene Potassium Silicate Zinc-rich Coatings","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCorrosion is the phenomenon which metal is destroyed by the interaction between metal and its environment in which it is located.(Q. H. Wang et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) According to relevant research reports, corrosion is becoming increasingly serious.(Vanaei, Eslami, and Egbewande \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2017\u003c/span\u003e) The economic and environmental problems caused by corrosion urgently need to be addressed. Coating protection is currently one of the most widely used and cost-effective anti-corrosion methods.(Wen Sun et al. 2021) Oil-based anti-corrosion coatings contain a large amount of volatile organic compounds (VOCs) that can cause significant harm to the environment and human body, (Wei, Cheng, and Li \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; H. Wang et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) while water-based inorganic zinc-rich coatings have the advantages of low VOCs emissions and easy cleaning after construction, which are deeply loved by people. (Liu, Zhan, and Li \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2012\u003c/span\u003e) Water-based potassium silicate zinc-rich anti-corrosion coating is one of them, but it has disadvantages such as poor water resistance, high zinc content which easily damage to the health of construction personnel. Therefore, it is necessary to improve the corrosion resistance of potassium silicate zinc-rich anti-corrosion coatings and reduce zinc content.\u003c/p\u003e \u003cp\u003eGraphene has good mechanical stability, low chemical reactivity, gas impermeability, and good barrier property(Wei, Cheng, and Li \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; H. Wang et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Wen Sun et al. 2021). It can be applied in anti-corrosion coatings. Cheng et al.(Cheng et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) prepared graphene/water-based potassium silicate zinc-rich coatings and studied the effect of graphene content on various performances of the coatings. The results indicated that water-based potassium silicate coating containing 2wt% graphene and 80wt% zinc particles can provide 40 days of cathodic protection for carbon steel substrates. However, its zinc content is still very high. This is because graphene has not fully utilized its excellent properties. It has a large specific surface area. (Chae, Siberio-P\u0026eacute;rez, and Kim \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) There are van der Waals forces and π - π bonds between the layers, making it easy to agglomerate and poor to disperse in coatings. (Yuan \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; Ollik and Lieder \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) Therefore, researchers often modify graphene to improve its anti-corrosion performance. Cai et al.(Cai, Zuo, and Luo \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) prepared polyaniline/graphene composites by in-situ polymerization, and uniformly dispersed them in water-borne polyurethane coatings. The results showed that the performance of coating which contained 0.75wt% polyaniline/graphene composite was better than that of 4wt% graphene. Xiao et al.(F. J. Xiao et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) prepared polyaniline/graphite oxide composite and doped it into water-borne epoxy acrylate zinc-rich coating to prepare polyaniline/graphite oxide water-borne epoxy acrylate zinc-rich coating. Research has shown that its corrosion resistance was better than that of coatings which was undoped. Nano-ZnO is known as a multifunctional material due to its unique physical and chemical properties, which has advantages such as good photocatalytic activity, high stability, environmental friendliness, and low price.(Rokhsat and Akhavan \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; M. Xiao, Lu, and Li \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; B and W 2012; Zhang, Huang, and Du \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) At present, there are few reports on the impact of Nano-ZnO/graphene composites on the anti-corrosion performance of water-based potassium silicate zinc-rich coatings.\u003c/p\u003e \u003cp\u003eIn this paper, graphene was prepared by chemical vapor deposition (CVD). Its surface was modified by Nano-ZnO in order to improve its dispersability in coatings and give full play to its excellent anti-corrosion performance. Nano-ZnO/graphene (Nano-ZnO/Gr) was added to potassium silicate zinc-rich coatings to prepare coatings with low zinc content and high corrosion resistance. This can provide a method for upgrading the anti-corrosion performance of potassium silicate zinc-rich coatings.\u003c/p\u003e"},{"header":"Experimental","content":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMaterials\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eMgO is analytically pure and prepared according to a reference. (Bai, Liu, and Liu 2005) Nitrogen and methane are purchased from Xi\u0026apos;an Longteng Chemical Co., Ltd. Zinc powder, zinc acetate, ethanol, hydrochloric acid, and sodium hydroxide are analytical reagents and purchased from China National Pharmaceutical Group Chemical Reagent Co., Ltd. Potassium silicate and alkaline silica sol are industrial grade and purchased from Guangzhou Yixin Chemical Co., Ltd. The silane coupling agent KH560 is industrial grade and purchased from Dinghai Plastic Chemical Co., Ltd. Dispersant 5040, defoamer EFKA2722, thickener, and leveling agent EFKA3777 are industrial grade and purchased from Shandong Yousuo Chemical Co., Ltd. Steel substrate are Q235 cold-rolled steel plate: 90 mm \u0026times; 50 mm \u0026times; 2 mm, purchased from Shenzhen Hongwang Mould Co., Ltd. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMethod\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePreparation of Graphene\u003c/p\u003e\n\u003cp\u003eInitially, magnesium oxide with a spherical morphology was extracted from dolomite ore by the Ammonium salt extracting method(Bai, Liu, and Liu 2005).\u0026nbsp;The quartz boat which contained 4.0 g MgO was placed in a tube furnace which was filled with nitrogen gas. When the temperature raised to 950 \u0026deg;C, methane was injected to the tube furnace at a flow rate of 1.5 L/min. The reaction was carried out at a constant temperature of 950 \u0026deg;C for 20 min. Then, the tube furnace cooled to room temperature. Nitrogen and methane were stopped injecting. The sample was take out from the tube furnace. 250 mL 4.0 mol/L hydrochloric acid solution was added to the sample. The mixture was stirred for 3 h and then washed with deionized water until there was no Cl-. It was dried in a oven at 60 \u0026deg;C for 24 h to obtain graphene (Gr).\u003c/p\u003e\n\u003cp\u003ePreparation of Nano-ZnO/Gr Composite\u003c/p\u003e\n\u003cp\u003e30 mL10% zinc acetate solution and 5 mL 0.4 g/mL graphene ethanol dispersion were mixed and stirred for 30 min. Its pH was adjusted to 11 with NaOH solution and then stirred for 2 h. The mixture was poured into a reactor and reacted in a oven at 120℃ for 18 h. Then it was washed with deionized water and ethanol, respectively, and dried for 2 h at 80 ℃. Nano-ZnO/Graphene composite was obtained which was a black powder.\u003c/p\u003e\n\u003cp\u003ePreparation of Nano-ZnO/Gr Potassium Silicate Zinc-rich Coating\u003c/p\u003e\n\u003cp\u003ePotassium silicate solution and alkaline silica sol solution were mixed in a 1:1 mass ratio, stirred at 45 ℃ for 2 h, and standed at room temperature to prepare potassium silicate base material with a modulus of 5.5. 3.0 g potassium silicate base material, 0.1 g thickener, 0.1 g leveling agent, 0.1 g defoamer, 0.1 g dispersant, and 0.2 g KH560 were added to 2.4 g deionized water. The mixture was stirred for 30 min to prepare component A. Different weights of Nano-ZnO/Gr (B component, wt.% of total component content: 0, 0.5, 1, 1.5, 2) and different amounts of zinc powder (C component, wt.% of total component content: 20, 30, 40, 50, 60, 70) were added to the component and stirred for 60 min to prepare a series of water-based potassium silicate zinc-rich coatings which contained different contents of Nano-ZnO/Gr and zinc powder.\u003c/p\u003e\n\u003cp\u003eNano-ZnO/Gr water-based potassium silicate zinc-rich coatings were uniformly applied on pretreated (polished, degreased) steel plate specimens by an automatic coating machine (thickness controlled at 90 \u0026plusmn;5\u0026mu;m). Then, it stood at room temperature for more than 24 h to obtain Nano-ZnO/Gr potassium silicate zinc-rich coatings.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eMain Instruments\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAFA-III automatic film applicator was used to prepare potassium silicate zinc-rich coatings at. Byes-60B precision brine spray testing machine was employed to test\u0026nbsp;corrosion\u0026nbsp;resistance\u0026nbsp;with the ISO 9227:2017 standard.\u0026nbsp;QFH-A pencil hardness tester was used to character hardness of coatings with\u0026nbsp;ISO 15184:2020 standard.\u0026nbsp;QFH-A baige knife was used to conduct grid cutting tests on the coating surface to measure the adhesion of the coating\u0026nbsp;with\u0026nbsp;ISO 2409:2020 standard.Quanta 200 scanning electron microscope\u0026nbsp;and\u0026nbsp;FEI-Tecnai G2 F20 Field emission transmission electron microscope\u0026nbsp;were\u0026nbsp;used to analysis the morphology of Nano-ZnO/grapheme. Tensor 27 infrared spectrometer was used to character the infrared spectra of graphene, Nano-ZnO, and Nano-ZnO/Gr.\u0026nbsp;The Contact Angle System with high-speed camera determined the contact angle of\u0026nbsp;coating surfaces.\u003c/p\u003e\n\u003cp\u003eAn electrochemical analyser (CHI660D) was used to measure the corrosion in 3.5% NaCl simulated seawater conditions. Three-point electrodes, which are the working electrode (coated steel plates), reference electrode (Ag/AgCl\u003csub\u003e2\u003c/sub\u003e), and counter electrode (platinum) were used for the corrosion test. Electrochemical impedance spectroscopy (EIS) was performed over a frequency range of 10\u003csup\u003e5\u003c/sup\u003e to 10\u003csup\u003e-2\u003c/sup\u003e Hz, while the dynamic potential polarization curve assessments were obtained at a scan rate of 1 mV/s, within a potential window of \u0026plusmn;300 mV relative to the open circuit potential. \u003c/p\u003e"},{"header":"Results and discussion","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStructural Characterization of Gr and Nano-ZnO/Gr\u003c/h2\u003e \u003cp\u003eCharacterization of graphene, as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, reveals a layered morphology in scanning electron microscopy (SEM) images, with graphene sheets (Gr) exhibiting a loosely stacked arrangement devoid of significant overlap (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e(a)). Transmission electron microscopy (TEM) further elucidates that these layers are composed of interwoven 50 nm independent microspheres(Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e(b)). Subsequent Brunauer-Emmett-Teller (BET) surface area and porosity analysis delineate a typical Type IV nitrogen adsorption-desorption isotherm, indicative of a mesoporous structure ((Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e(c)). Analysis infers the presence of approximately 1 nm micropores within the smallest microsphere units, yielding a surface area of 312.12 m\u003csup\u003e2\u003c/sup\u003e/g and an average pore size of 30.79 nm((Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e(d)).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e (a) presents the SEM image of Nano-ZnO/Gr composite. Graphene appears in a sheet-like form. Granular nano ZnO particles are uniformly dispersed on the surface of graphene. Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e (b) showed the infrared spectra of graphene, Nano-ZnO, and Nano-ZnO/Gr. Nano-ZnO exhibited a strong absorption peak at 453 cm\u003csup\u003e-1\u003c/sup\u003e, which was an asymmetric stretching vibration peak of the Zn-O bond. The absorption peak of graphene at 1640 cm\u003csup\u003e-1\u003c/sup\u003e was the stretching vibration peak of the C\u0026thinsp;=\u0026thinsp;C double bond. The absorption peak at 1053 cm\u003csup\u003e-1\u003c/sup\u003e was the stretching vibration peak of the C\u0026thinsp;=\u0026thinsp;O double bond. The absorption peak at 3462 cm\u003csup\u003e-1\u003c/sup\u003e was the stretching vibration peak of the -O-H bond, indicating the presence of oxygen-containing functional groups on the graphene. The infrared spectrum of Nano-ZnO/Gr showed characteristic absorption peaks of Nano-ZnO and graphene. The shape of the absorption peak at 453 cm\u003csup\u003e-1\u003c/sup\u003e became wide. Meanwhile, the intensity of the absorption peak at 3462 cm\u003csup\u003e-1\u003c/sup\u003e weakened. These indicated that there was the interaction between Nano-ZnO and graphene. Therefore, the Nano-ZnO/Gr composite was formed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003ePerformances of Nano-ZnO/Gr Potassium Silicate Zinc-rich Coatings\u003c/h2\u003e \u003cdiv id=\"Sec11\" class=\"Section3\"\u003e \u003ch2\u003eCoating Adhesion Test\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e showed the adhesion test diagram of coatings containing zinc and Nano-ZnO/Gr with different mass fractions. When the Zn and Nano-ZnO/Gr content were 30wt% and less than or equal 1.5wt%, respectively, the adhesion of the coatings were optimal because graphene acted as adhesion promoters for the steel substrate, resulted in firmly binding to the substrate with coating(S. G. Wang et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). When the content of Nano-ZnO/Gr was too high, its dispersibility in the potassium silicate matrix was poor, which easily leaded to Nano-ZnO/Gr aggregate. When the zinc content was greater than 60wt%, the coating which contained Nano-ZnO/Gr did not meet the standard of the adhesion. Therefore, the performances of coatings with 60wt% and 70wt% zinc content would no longer be studied.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eCoating hardness test\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e showed the hardness test results of coatings with different content of zinc powder and Nano-ZnO/Gr. It can be seen that when the zinc content and Nano ZnO/Gr content were 30wt% and 1wt%, respectively, the hardness of the coating reached the maximum hardness grade up to 4H. This was because both zinc powder and ZnO of the Nano-ZnO/Gr composite reacted with Si-O bonds. Meanwhile, the Nano-ZnO/Gr composite was used as filler to fill micropores and flaws of the coatings. (W. Sun et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) Therefore, the coating with high density and hardness was formed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eContact angle testing of coating surfaces\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e showed the contact angle test of coatings with Nano-ZnO/Gr. It can be seen that as the content of Nano-ZnO/Gr increased, the contact angle of coatings with different zinc contents first increased and then decreased. When the coating contained 30wt% zinc and 1wt% Nano-ZnO/Gr, its contact angle increased from 42\u0026deg; to 75.8\u0026deg;, indicating excellent hydrophobicity. This can be attributed to the good dispersibility of Nano-ZnO/Gr in silicate matrix which can make the coating surface smoother and more uniform.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eCoating corrosion resistance test\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e showed the water resistance test diagram of coatings with Nano-ZnO/Gr. It can be seen that the coating with 30wt% zinc and 1wt% Nano-ZnO/Gr exhibited the best water resistance. This was because the zinc powder and Nano-ZnO/Gr in the coating were fully mixed with the potassium silicate matrix to form a dense coating. Furthermore, the Nano-ZnO/Gr flakes formed a tortuous diffusion pathway, which prevent water from reaching the substrate surface.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eElectrochemical analysis of coatings\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e showed the potentiodynamic polarization curves of coatings with Nano-ZnO/Gr soaked in 3.5% NaCl solution for 12 h. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e showed the parameters obtained from the corresponding potentiodynamic polarization curves in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e. It can be seen that the \u003cem\u003eE\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e of the steel plate sample coated with Nano-ZnO/Gr potassium silicate zinc-rich coating significantly increases, while the \u003cem\u003ei\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e substantially decreased, indicating that the coating with Nano-ZnO/Gr had good anticorrosion resistance. From the data in the Table\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, it can be seen that when the coating contained 30wt% zinc and 1wt% Nano-ZnO/Gr, its \u003cem\u003ei\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e was the smallest, decreasing to 7.82\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e A/cm\u003csup\u003e2\u003c/sup\u003e, with a larger \u003cem\u003eE\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e of -0.589 V, indicating the coating had the best corrosion resistance among them. Zinc oxide on graphene sheets can reduce graphene clusters. At the same time, it has a certain polarity and can interact with the substrate, making graphene more evenly dispersed in aqueous potassium silicate coatings. This fully utilizes the barrier effect and conductivity of graphene, thereby improving the utilization efficiency of zinc powder. When the content of Nano-ZnO/Gr exceeded 1%, graphene would aggregate which can reduce its anti-corrosion performance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe parameters obtained from polarization curves of coatings with different zinc content and Nano-ZnO/Gr content\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026times;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZinc(wt%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNano-ZnO/Gr(wt%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eE\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e(V)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ei\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e(A/cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBare steel\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e3.33\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;4\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e6.45\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e7.31\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e9.07\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.07\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.81\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.11\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.54\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e7.80\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.87\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e2.42\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.25\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e5.39\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e1.86\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e3.60\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e5.22\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e8.63\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e2.59\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e3.48\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e9.05\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026times;\" colname=\"c4\"\u003e \u003cp\u003e2.11\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e illustrates the impedance spectra of coatings with Nano-ZnO/graphene composite which were immersed in 3.5% NaCl solution for 24 h, including Bode and Nyquist plots. Figure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e showed the impedance mode values (|\u003cem\u003eZ\u003c/em\u003e|\u003csub\u003e0.01Hz\u003c/sub\u003e) of the coating at 0.01 Hz obtained from the Bode plot. Figure\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e showed the coating charge transfer resistance (\u003cem\u003eR\u003c/em\u003e\u003csub\u003ect\u003c/sub\u003e) data obtained from the Nyquist plot. It can be seen that the coating with 30wt% zinc and 1wt% Nano-ZnO/Gr content of had the maximum |\u003cem\u003eZ\u003c/em\u003e|\u003csub\u003e0.01Hz\u003c/sub\u003e and \u003cem\u003eR\u003c/em\u003e\u003csub\u003ect\u003c/sub\u003e, reaching 3.069\u0026times;10\u003csup\u003e4\u003c/sup\u003e Ω\u0026middot;cm2 and 3.045\u0026times;10\u003csup\u003e4\u003c/sup\u003e Ω\u0026middot;cm\u003csup\u003e2\u003c/sup\u003e, respectively. This was consistent with the previous physical performances and electrochemical testing of the coatings.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eNano-ZnO/Gr composites were prepared by hydrothermal synthesis method and studied their effect on the anti-corrosion performances of potassium silicate zinc-rich coatings. When the zinc power and Nano-ZnO/Gr content were 30wt% and 1wt%, respectively, the potassium silicate zinc-rich coating exhibited the excellent anti-corrosion performance with adhesion of grade 1, hardness of 4H, \u003cem\u003eE\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e of -0.589 V, \u003cem\u003ei\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e of 7.82\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;7\u003c/sup\u003e A/cm\u003csup\u003e2\u003c/sup\u003e, |\u003cem\u003eZ\u003c/em\u003e|\u003csub\u003e0.01Hz\u003c/sub\u003e of 2.62\u0026times;10\u003csup\u003e4\u003c/sup\u003e Ω\u0026middot;cm\u003csup\u003e2\u003c/sup\u003e, \u003cem\u003eR\u003c/em\u003e\u003csub\u003ect\u003c/sub\u003e of 2.91\u0026times;10\u003csup\u003e4\u003c/sup\u003e Ω\u0026middot;cm\u003csup\u003e2\u003c/sup\u003e. Compared with the neat coating, the physical and electrochemical properties of potassium silicate zinc-rich coating containing Nano-ZnO/Gr were significantly polished, exhibiting long-term corrosion resistance. Furthermore, its zinc content was greatly reduced. This study indicated that doping appropriate amount of Nano-ZnO/Gr composites into potassium silicate zinc rich coatings can effectively enhance the excellent anti-corrosion performance of graphene in coatings and the utilization rate of zinc powder due to tortious diffusion pathways and a better electrical connection between zinc particles and steel substrate. This method is a simple and efficient way to improve the anti-corrosion performance of water-based potassium silicate zinc-rich coatings.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u003c/strong\u003e They contribute 100% to the study work\u0026apos;s development, from experimentation to analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThere is no money available for this project.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe authors confirm that the data supporting this study\u0026apos;s conclusions is included in the publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u0026nbsp;\u003c/strong\u003eThere are no conflicting interests to disclose in this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcceptance of ethics:\u0026nbsp;\u003c/strong\u003eBecause this experiment does not involve people or animals, no ethics committee approval is required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent of participants:\u0026nbsp;\u003c/strong\u003eBecause this study does not include people or animals, no permission is required to participate.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePublishing permission:\u0026nbsp;\u003c/strong\u003eThe writers grant their permission for the work to be published by the publisher. Consent to publish: The authors give the publisher the consent to publish the work.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAcknowledgments.\u0026nbsp;\u003c/strong\u003eThis research received no external funding.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eB, Kumar, and Kim S. 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Du. 2020. \u0026ldquo;Preparation and Anti-Mold Properties of Nano-ZnO/Poly(N-Isopropylacrylamide) Com-Posite Hydrogels.\u0026rdquo; \u003cem\u003eMolecules\u003c/em\u003e 25 (18): 4135\u0026ndash;44. https://doi.org/10.3390/molecules25184135.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"chemical-papers","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chpa","sideBox":"Learn more about [Chemical Papers](http://link.springer.com/journal/11696)","snPcode":"11696","submissionUrl":"https://www.editorialmanager.com/CHPA/default.aspx","title":"Chemical Papers","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Potassium silicate zinc-rich coating, Graphene, Nano-ZnO, Corrosion resistance","lastPublishedDoi":"10.21203/rs.3.rs-4209341/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4209341/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eNano-ZnO/graphene composites were prepared and added to potassium silicate zinc-rich coatings in order to obtain Nano-ZnO/graphene potassium silicate zinc-rich anti-corrosion coatings. Their morphology and corrosion resistance were charactered by scanning electron microscopy, electrochemical testing, and salt spray testing. The effect of Nano-ZnO/grapheme contents on the anticorrosion performance of coatings was also studied. Compared to neat water-based potassium silicate zinc-rich coatings with 50wt% zinc, Nano-ZnO/graphene potassium silicate zinc-rich coating with 30wt% zinc and 1wt% Nano-ZnO/graphene has better corrosion resistance. Their water resistance and \u003cem\u003eE\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e are improved, \u003cem\u003ei\u003c/em\u003e\u003csub\u003ecorr\u003c/sub\u003e is reduced by one order of magnitude, |\u003cem\u003eZ\u003c/em\u003e|\u003csub\u003e0.01Hz\u003c/sub\u003e is increased by six times, and \u003cem\u003eR\u003c/em\u003e\u003csub\u003ect\u003c/sub\u003e is increased by three times. This study indicates that Nano-ZnO/graphene not only enhances anti-corrosion performance of potassium silicate zinc-rich anti-corrosion coatings, but also improves the utilization rate of zinc powder.\u003c/p\u003e","manuscriptTitle":"Preparation and Performances Study of Nano-ZnO/Graphene Potassium Silicate Zinc-rich Coatings","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-09 09:31:44","doi":"10.21203/rs.3.rs-4209341/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2024-04-10T13:21:29+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-04-05T07:09:21+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Chemical Papers","date":"2024-04-04T09:24:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-04-04T08:48:31+00:00","index":"","fulltext":""},{"type":"submitted","content":"Chemical Papers","date":"2024-04-02T22:06:29+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"chemical-papers","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"chpa","sideBox":"Learn more about [Chemical Papers](http://link.springer.com/journal/11696)","snPcode":"11696","submissionUrl":"https://www.editorialmanager.com/CHPA/default.aspx","title":"Chemical Papers","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"f0d985da-e1fb-476e-a8ed-08e0005f3ebc","owner":[],"postedDate":"April 9th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-09-04T17:21:59+00:00","versionOfRecord":{"articleIdentity":"rs-4209341","link":"https://doi.org/10.1007/s11696-024-03645-6","journal":{"identity":"chemical-papers","isVorOnly":false,"title":"Chemical Papers"},"publishedOn":"2024-08-20 15:57:53","publishedOnDateReadable":"August 20th, 2024"},"versionCreatedAt":"2024-04-09 09:31:44","video":"","vorDoi":"10.1007/s11696-024-03645-6","vorDoiUrl":"https://doi.org/10.1007/s11696-024-03645-6","workflowStages":[]},"version":"v1","identity":"rs-4209341","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4209341","identity":"rs-4209341","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}