Study on Mitigating Membrane Degradation in Degraded Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cell through Temperature and Humidity Control

Study on Mitigating Membrane Degradation in Degraded Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cell through Temperature and Humidity Control | 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 Study on Mitigating Membrane Degradation in Degraded Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cell through Temperature and Humidity Control Seungtae Lee, Sohyeong Oh, Donggeun Yoo, Kwon Pil Park This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4648374/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 25 Nov, 2024 Read the published version in Korean Journal of Chemical Engineering → Version 1 posted 5 You are reading this latest preprint version Abstract Polymer electrolyte membrane fuel cells (PEMFCs) have faced challenges in achieve their lifespan goals due to the degradation of the membrane electrode assembly (MEA) during long-term operation. To enhance the durability of PEMFCs, it is necessary to research materials that can improve the durability of the membrane and electrodes, as well as to study operating conditions that can reduce degradation. This paper investigated methods to mitigate the membrane degradation of electrochemically degraded MEAs by controlling humidity and temperature among the operating conditions. MEA was degraded electrochemically by conducting open circuit voltage (OCV) holding, and then the degradation rate according to temperature and humidity changes was observed through fluoride emission rate (FER) change. In a degraded MEA, it is shown that increasing cell humidity accelerates membrane degradation. According to linear sweep voltammetry (LSV) results, this was confirmed to be due to the increase in hydrogen permeability caused by the higher humidity. The decrease in temperature lowered the rate of membrane degradation, which is attributed to a decrease in the rate of radical attack and generation resulting from the temperature decrease. Therefore, it was confirmed that to mitigate membrane degradation in electrochemically degraded MEAs, it is effective to reduce temperature and humidity, thereby decreasing the rate of radical formation. PEMFC electrochemical degradation mitigating degradation hydrogen crossover Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 1. Introduction A fuel cell is an eco-friendly energy conversion device that transforms the chemical energy of hydrogen into electrical energy. As global warming is growing, the need for eco-friendly energy is increasing. Polymer electrolyte membrane fuel cell (PEMFC) has advantages such as high current density, fast start-up, and low operating temperature, making it applicable in various fields from stationary to transportation uses. Currently, the required lifespan of PEMFCs ranges from 5,000 to 40,000 hours depending on the application [ 1 ]. However, due to the degradation of the membrane electrode assembly (MEA) during long-term operation, these lifespan goals are not being met [ 2 – 7 ]. The degradation of the MEA is classified into electrode degradation and electrolyte membrane degradation. Electrode degradation includes catalyst degradation caused by the dissolution and sintering of Pt during load cycling [ 8 ], as well as the degradation of carbon supports by high temperature and high potential [ 9 , 10 ]. Membrane degradation includes mechanical degradation due to humidification/drying and electrochemical degradation due to formation of radicals at a high potential [ 11 ]. To enhance the durability of each material, various studies have been conducted [ 12 – 18 ]. To improve electrode durability, alloy catalysts [ 19 ] and N-doped carbon [ 13 ] and graphited carbon [ 15 ] are used. To improve the durability of the membrane, radical scavengers are added to the membrane [ 14 ], and a e-PTFE support is impregnated within the membrane [ 16 ]. Another way to improve durability is by adjusting the cell operating conditions to mitigate degradation. The degradation characteristics of the membrane and electrode in the MEA change depending on operating conditions such as temperature, humidity, voltage, and pressure. Particularly, the degradation rate of the electrolyte membrane accelerates when it is already degraded. Therefore, the strategy to mitigate membrane degradation in degraded MEAs is important. This study aims to investigate operating conditions that reduce the degradation rate of electrochemically degraded MEAs. We conducted open circuit voltage (OCV) holding to electrochemically deteriorate MEA and observed changes in the membrane degradation rate while adjusting humidity and temperature. During OCV holding, the irreversible degradation of the MEA is analyzed by measuring cyclic voltammetry (CV) and linear sweep voltammetry (LSV), and the membrane degradation rate is monitored by the fluoride emission rate (FER). 2. Experimental 2.1 Fabrication of MEA MEAs were fabricated by sandwiching the membrane and electrodes and then hot pressing them with at 120°C with 100 kg/cm 2 . The polymer membranes used were Nafion 211 (Dupont, USA) and Nafion XL (Dupont, USA), and the electrode catalyst was Pt/C, with a loading amount of 0.4 mg/cm² for both the anode and cathode. 2.2 Single cell preparation. The cell was assembled using the MEA, gas diffusion layers (sigracet 39BB, SGL carbon, Germany) and a gasket. The bipolar plates are made of graphite, and the flow field has a 5-channel serpentine structure with an area of 25 cm 2 . The cell operation was performed on a test station (CNL Energy, Korea), and the cell temperature, humidity, and gas flow rate were controlled. 2.3 Durability test OCV holding was performed as an electrochemical durability test, conducted at 90°C and 30% RH, with hydrogen and oxygen supplied to the anode and cathode, respectively, at a flow rate of 829 ml/min. During OCV holding, the irreversible membrane degradation of the MEA was monitored through hydrogen crossover current density (HCCD) and FER changes. After observing the irreversible degradation of the electrolyte membrane, the durability test conditions were adjusted to temperatures and humidity of 90 − 60°C and 30–60% relative humidity (RH) to observe changes in the membrane degradation rate. 2.4 Characterization In this experiment, all characterization analyses were conducted under cell conditions of 70°C and 100% RH. I-V curve was measured under atmospheric pressure, supplying H 2 and air to the anode and cathode with stoichiometries of 1.5 and 2.0, respectively. CV and LSV were conducted using potentiostat (SI 1287, Solatron, Germany). During CV and LSV measurements, hydrogen and argon were supplied to the anode and cathode of the cell, respectively. CV measurements were conducted for 15 cycles at a scan rate of 30 mV/s in the potential range of 0.05 ~ 1.2 V. The electrochemical surface area (ECSA) was calculated using the current density from the 0-0.4 V hydrogen desorption region as the area above the trend line in the 0.4 V electric double layer region. LSV was conducted to observe the change of HCCD and short resistance (SR). HCCD was represented by the current density value at 0.3 V, obtained by sweeping the potential at a scan rate of 1 mV/s over the range of 0 to 0.5 V. SR was calculated as the reciprocal of the slope between voltage and current density from 0.4 to 0.5 V, while by sweeping at a scan rate of 0.5 mV/s over the range of 0.3 to 0.5 V. 2.5 Fluoride emission rate The FER was measured quantitatively using the Ion Selective Electrode Meter (PH-250L, ISTEK, Korea). The calibration curve was prepared with a sodium fluoride 1000 − 100 ppm standard solution. The condensate was collected by condensing the gas coming out of the cell outlet. 3. Results and discussion 3.1 Electrochemical degradation of MEA OCV holding was conducted to degrade the electrolyte membrane electrochemically (Fig. 1). During OCV holding, the cell voltage decreases with time. The decreasing voltage can be divided into reversible voltage decrease, which recovers after activation, and irreversible voltage decrease, which does not recover after activation [ 20 ]. During the OCV holding 48 h, the decreased voltage mostly recovered after activation and characterization, indicating that mostly reversible degradation occurred in the early stages of degradation. However, starting from OCV holding 96 h, some irreversible degradation began to appear, where the decreased voltage did not fully recover. As the durability test progressed, the voltage decreases due to irreversible degradation increased gradually, and at OCV holding for 192 h, the cell voltage decreased to 0.896 V. Figure 2 shows the change in FER during OCV holding durability evaluation. FER indicates the variation of fluoride ions emitted from the membrane by electrochemical degradation during OCV holding. Therefore, the change in FER reflects the irreversible degradation of the membrane. The FER consistently increases, reaching 0.0287 µmol/hr cm 2 at OCV holding 192 h. It shows that the irreversible degradation rate gradually increases as the durability test progresses. The electrochemical degradation of membrane occurs due to radicals formed during the process of hydrogen or oxygen permeating through the membrane and undergoing oxygen reduction reaction (ORR) on the catalyst surface [ 11 , 21 ]. Therefore, the increase in FER during the durability test is related to the radical generation rate. 1) When the membrane thickness decreases due to electrochemical degradation and gas permeability increases, the rate of radical generation increases. However, in this case, the HCCD is constant until OCV holding 144 h (Fig. 3b). 2) The high voltage during OCV holding can lead to electrode catalyst degradation, causing ECSA decrease, and platinum dissolution and deposition inside the membrane. Pt deposited in the membrane can accelerate the electrochemical degradation by generating radicals within the membrane [ 20 , 22 , 23 ]. Figure 4 shows the change of CV and ECSA during OCV holding. The ECSA decreases steadily during the durability test. The high voltages formed during OCV holding can lead to catalyst degradation in the MEA. Therefore, it is speculated that the increasing irreversible membrane degradation rate over time is likely due to catalyst degradation occurring during OCV holding. Figure 3b shows HCCD changes during durability test. The HCCD variation serves as an indicator of membrane degradation. As the membrane undergoes electrochemical degradation, its thickness decreases, resulting in an increase in HCCD [ 24 ]. During OCV holding 144 h, there were no significant changes in HCCD, but after 192 h, the HCCD increased by approximately 30.4% to 2.23 mA/cm 2 . Therefore, the result shows that the membrane was irreversibly deteriorated after OCV holding 192 h. Figure 3c shows the variation in SR during the durability test, demonstrating a steady decline. The decrease in SR is influenced not only by the thinning of the membrane but also by electrode degradation. High voltage of OCV can cause Pt catalyst dissolution, leading to Pt deposition into the membrane. Platinum deposited inside the membrane creates paths for electron flow, thereby reducing SR. These results indicate that the MEA experienced irreversible degradation of both the membrane and electrodes during OCV holding. Figure 5 shows the I-V curves of the MEA during OCV holding. The OCV of the MEA decreased from an initial 0.950 V to 0.929 V after the OCV holding 192 h. The OCV is mainly influenced by HCCD and SR. Hydrogen crossover from the anode to the cathode forms a mixed potential at the cathode, thereby decreasing the cell voltage. When the SR decreases, parasitic current increases, resulting in a decrease in cell voltage. In this case, the SR remains above 1 kΩ・cm 2 until OCV holding 192 h (Fig. 3c). Therefore, the increase of HCCD is the main cause of OCV reduction. Furthermore, the current density at 0.6 V decreased from 1264.4 mA/cm 2 to 1077.9 mA/cm 2 after OCV holding 192 h. The decrease in MEA performance is attributed to catalyst degradation. Consequently, we confirmed that the MEA had undergone sufficient irreversible degradation through changes in LSV and OCV. After OCV holding 192 h, we studied operation conditions that could mitigate the degradation rate of the degraded MEA. 3.2 Mitigating degradation by controlling humidity and temperature in degraded MEA As humidity decreases, the polymer electrolyte membrane of PEMFCs becomes susceptible to the degradation of sulfonic acid groups [ 11 ]. One way to reduce the degradation rate of the membrane is to increase the humidity of the cell during degradation. Therefore, we conducted the OCV holding at 60% RH, which is higher compared to 30% RH. After the increasing humidity, the rate of OCV decrease accelerated to 2.3 mV/h [Fig. 6]. Additionally, FER showed a rapid increase [Fig. 7]. The increase in the degradation rate was also clearly evident in changes in HCCD and SR. HCCD increased to 5.76 mA/cm 2 after increasing humidity during OCV holding, and SR decreased to 0.465 kΩ·cm 2 . These results show that increasing the cell humidity in a degraded MEA significantly accelerates the rate of irreversible membrane degradation. Generally, increasing RH mitigates the membrane degradation by radicals. However, the increase in moisture within the membrane leads to a higher dissolution and diffusion rate of hydrogen through water [ 25 ], which can increase the rate of radical formation and accelerate membrane degradation. Therefore, it is speculated that the increase in the rate of radical formation is the cause of the increase in the rate of irreversible degradation. The changes in permeability of the degraded MEA depending on RH are discussed in section 3.3 . After OCV holding 240 h, we reduced the cell temperature from 90°C to 60°C to conduct OCV holding and observed changes in degradation rate. Following the cell temperature reduction, the FER during OCV holding sharply decreased to 0.0030 µmol/hr cm 2 . Additionally, the increases in HCCD and decreases in SR were less pronounced compared to when humidity was increased (Fig. 8). This reduction in degradation rate can be attributed to the decrease in radical generation rate and reaction rate as the cell temperature decreases. The degradation of the polymer membrane can be considered as a two-step process involving radical generation reaction and polymer degradation reaction caused by radicals. Both reactions can be expressed by the general Arrhenius equation [ 26 ]. Thus, the phenomenon of a sharp decrease in membrane degradation rate with decreasing temperature can be explained by the exponential decrease in reaction rate as temperature decreases. After OCV holding 268 h, a durability test was conducted by reducing the humidity from 60–30% at 60°C to observe the degradation rate at low temperature and low humidity. The overall deterioration mitigation effect was less pronounced after reducing the humidity compared to lowering the temperature. Nevertheless, the degradation mitigation effect due to humidity reduction was still significant. The FER at 60°C with 30% RH decreased even further compared to that at 60°C with 60% RH, indicating a further reduction in degradation rate (Fig. 7). Furthermore, the increase in HCCD and the decrease in SR were also reduced. Reduced humidity makes the polymer membrane more susceptible to radical attacks, but in degraded MEAs, humidity reduction repeatedly mitigated the membrane degradation rate. These results suggest that in degraded MEAs, the stage of radical formation may have a greater impact on membrane degradation than the stage where radicals attack the membrane in the two-stage process of polymer membrane degradation. 3.3 Changes in HCCD with varying humidity in degraded MEA In degraded MEA, increased humidity accelerated the rate of irreversible membrane degradation. This result appears to be due to the increased gas crossover in the MEA under higher humidity. To confirm this, the changes in hydrogen permeability of the MEA before and after degradation were measured as a function of humidity. Since degraded MEAs are susceptible to mechanical stress induced by humidity changes, we used a reinforced MEA with dimensional stability. The reinforced MEA was electrochemically degraded in the same way by applying OCV holding (Fig. 9). The HCCD of the reinforced MEA increase from 1.02 to 8.42 mA/cm 2 during OCV holding 144 h. The changes in HCCD with humidity before and after the degradation of the reinforced MEA are shown in Fig. 10. When the RH was raised from 20–60%, the HCCD increased from 1.04 mA/cm² to 1.35 mA/cm² in the MEA before degradation and from 5.04 mA/cm² to 6.73 mA/cm² in the MEA after degradation (Fig. 10). The HCCD of MEAs before and after degradation increased approximately 30% with rising cell humidity. However, the absolute value of the increased HCCD was about five times higher in the degraded MEA. This result shows that the HCCD of degraded MEA is more sensitive to changes in humidity. Therefore, as mentioned in section 3.2 , the increased membrane degradation rate with higher humidity in the degraded MEA is interpreted to be due to the increased HCCD. 4. Conclusions In this study, we investigated the temperature and humidity conditions that mitigate the membrane degradation rate in electrochemically degraded MEAs. The MEA was degraded by performing OCV holding for 192 h, after which we observed changes in degradation rates by varying the temperature and humidity. When the cell humidity was increased from 30% RH to 60% RH, a rapid increase in FER, HCCD, and SR was observed. Although an increase in RH reduces membrane degradation caused by radicals, in degraded MEAs, the rise in RH led to higher hydrogen permeability, which in turn elevated the rate of radical generation, ultimately resulting in an accelerated membrane degradation rate. Durability test conducted at 60°C, 60% RH by lowering the cell temperature showed a decrease in OCV decay rate and FER. Additionally, the rates of HCCD increase and SR decrease were also reduced. This result indicates that temperature reduction led to a decrease in degradation rate caused by radicals. Subsequently, conducting durability evaluation at 60°C and 30% RH by lowering both temperature and humidity resulted in the lowest membrane degradation rate observed. Ultimately, it was confirmed that reducing temperature and humidity, which can decrease radical formation rate, is effective in mitigating membrane degradation in electrochemically degraded MEAs. Declarations ACKNOWLEDGEMENTS This work was supported by the Technology Innovation Program (20011633) funded By the Ministry of Trade, Industry & Energy (MOTIE, Korea). References DOE U.S. DOE fuel cell technologies office multi-year research, development, and demonstration plan. 3.4 fuel cells (2016), https://www.energy.gov/sites/default/files/2017/05/f34/ fcto_myrdd_ fuel_ cells. pdf. Accessed 27 June 202 4 D.E. Curtin, R.D. Lousenberg, T.J. Henry, P.C. Tangeman, M.E. Tisack, Journal of power Sources, 131 (2004) 41–48. S.D. Knights, K.M. Colbow, J. St-Pierre, D.P. Wilkinson, Journal of power sources, 127 (2004) 127–134. Z. 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Cite Share Download PDF Status: Published Journal Publication published 25 Nov, 2024 Read the published version in Korean Journal of Chemical Engineering → Version 1 posted Editorial decision: Major Revisions Needed 06 Aug, 2024 Reviewers agreed at journal 07 Jul, 2024 Reviewers invited by journal 02 Jul, 2024 Editor assigned by journal 01 Jul, 2024 First submitted to journal 27 Jun, 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-4648374","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":321979931,"identity":"cbd55730-afa6-4159-9eb8-853a3e946a46","order_by":0,"name":"Seungtae Lee","email":"","orcid":"","institution":"Sunchon National University","correspondingAuthor":false,"prefix":"","firstName":"Seungtae","middleName":"","lastName":"Lee","suffix":""},{"id":321979932,"identity":"b760be7d-575b-4ceb-ad17-249ac1a112c1","order_by":1,"name":"Sohyeong Oh","email":"","orcid":"","institution":"Sunchon National 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4","display":"","copyAsset":false,"role":"figure","size":35136,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of (a) CV, and (b) ECSA during OCV holding.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/947b3b14efbfe15385efefae.png"},{"id":61102854,"identity":"16144a6f-7509-45a7-bae8-9b03de4e6e40","added_by":"auto","created_at":"2024-07-25 15:24:17","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":31736,"visible":true,"origin":"","legend":"\u003cp\u003eI-V curves during OCV holding.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/fda842419ac50b69f274a73c.png"},{"id":61102170,"identity":"713e7a07-b682-4add-b1ed-ba15ff841e92","added_by":"auto","created_at":"2024-07-25 15:16:17","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":67950,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of voltage according to humidity and temperature control during OCV holding.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/9a2af614899bc7a2f0a42427.png"},{"id":61103857,"identity":"062d8682-0ca4-474d-bef7-5fc1051a6275","added_by":"auto","created_at":"2024-07-25 15:40:17","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":86366,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of FER according to humidity and temperature control during OCV holding.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/2f0c191c5eedf8b39b19b309.png"},{"id":61103297,"identity":"c2946089-54da-45fc-b01f-807a9820ca19","added_by":"auto","created_at":"2024-07-25 15:32:17","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":96441,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of (a) HCCD, and (b) SR according to humidity and temperature control during OCV holding.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/2b0a21cc263db30d77b37f5f.png"},{"id":61102177,"identity":"5c1197ce-37b0-4a20-b6f5-d218c8609e3b","added_by":"auto","created_at":"2024-07-25 15:16:17","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":43583,"visible":true,"origin":"","legend":"\u003cp\u003eVariation of (a) OCV, and (b) change of LSV during OCV holding.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/850fd8696897e9104058d752.png"},{"id":61102175,"identity":"e789ee0b-c9d8-45bd-91ee-625e44eca270","added_by":"auto","created_at":"2024-07-25 15:16:17","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":85921,"visible":true,"origin":"","legend":"\u003cp\u003eLSV according to humidity of MEA before and after MEA degradation (a) before degradation (b) after degradation. (c) Change of HCCD according to RH.\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/e95faf80a1364a6284ee288c.png"},{"id":70382819,"identity":"79e79916-2e4f-4678-be3c-2c62ca66fa42","added_by":"auto","created_at":"2024-12-02 16:32:00","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":777194,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4648374/v1/ed6758ee-064e-4a3f-9f15-61022ffe5605.pdf"}],"financialInterests":"","formattedTitle":"Study on Mitigating Membrane Degradation in Degraded Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cell through Temperature and Humidity Control","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eA fuel cell is an eco-friendly energy conversion device that transforms the chemical energy of hydrogen into electrical energy. As global warming is growing, the need for eco-friendly energy is increasing. Polymer electrolyte membrane fuel cell (PEMFC) has advantages such as high current density, fast start-up, and low operating temperature, making it applicable in various fields from stationary to transportation uses. Currently, the required lifespan of PEMFCs ranges from 5,000 to 40,000 hours depending on the application [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, due to the degradation of the membrane electrode assembly (MEA) during long-term operation, these lifespan goals are not being met [\u003cspan additionalcitationids=\"CR3 CR4 CR5 CR6\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe degradation of the MEA is classified into electrode degradation and electrolyte membrane degradation. Electrode degradation includes catalyst degradation caused by the dissolution and sintering of Pt during load cycling [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], as well as the degradation of carbon supports by high temperature and high potential [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Membrane degradation includes mechanical degradation due to humidification/drying and electrochemical degradation due to formation of radicals at a high potential [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. To enhance the durability of each material, various studies have been conducted [\u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16 CR17\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. To improve electrode durability, alloy catalysts [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] and N-doped carbon [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] and graphited carbon [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] are used. To improve the durability of the membrane, radical scavengers are added to the membrane [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], and a e-PTFE support is impregnated within the membrane [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAnother way to improve durability is by adjusting the cell operating conditions to mitigate degradation. The degradation characteristics of the membrane and electrode in the MEA change depending on operating conditions such as temperature, humidity, voltage, and pressure. Particularly, the degradation rate of the electrolyte membrane accelerates when it is already degraded. Therefore, the strategy to mitigate membrane degradation in degraded MEAs is important.\u003c/p\u003e \u003cp\u003eThis study aims to investigate operating conditions that reduce the degradation rate of electrochemically degraded MEAs. We conducted open circuit voltage (OCV) holding to electrochemically deteriorate MEA and observed changes in the membrane degradation rate while adjusting humidity and temperature. During OCV holding, the irreversible degradation of the MEA is analyzed by measuring cyclic voltammetry (CV) and linear sweep voltammetry (LSV), and the membrane degradation rate is monitored by the fluoride emission rate (FER).\u003c/p\u003e"},{"header":"2. Experimental","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Fabrication of MEA\u003c/h2\u003e \u003cp\u003eMEAs were fabricated by sandwiching the membrane and electrodes and then hot pressing them with at 120\u0026deg;C with 100 kg/cm\u003csup\u003e2\u003c/sup\u003e. The polymer membranes used were Nafion 211 (Dupont, USA) and Nafion XL (Dupont, USA), and the electrode catalyst was Pt/C, with a loading amount of 0.4 mg/cm\u0026sup2; for both the anode and cathode.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Single cell preparation.\u003c/h2\u003e \u003cp\u003eThe cell was assembled using the MEA, gas diffusion layers (sigracet 39BB, SGL carbon, Germany) and a gasket. The bipolar plates are made of graphite, and the flow field has a 5-channel serpentine structure with an area of 25 cm\u003csup\u003e2\u003c/sup\u003e. The cell operation was performed on a test station (CNL Energy, Korea), and the cell temperature, humidity, and gas flow rate were controlled.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Durability test\u003c/h2\u003e \u003cp\u003eOCV holding was performed as an electrochemical durability test, conducted at 90\u0026deg;C and 30% RH, with hydrogen and oxygen supplied to the anode and cathode, respectively, at a flow rate of 829 ml/min. During OCV holding, the irreversible membrane degradation of the MEA was monitored through hydrogen crossover current density (HCCD) and FER changes. After observing the irreversible degradation of the electrolyte membrane, the durability test conditions were adjusted to temperatures and humidity of 90\u0026thinsp;\u0026minus;\u0026thinsp;60\u0026deg;C and 30\u0026ndash;60% relative humidity (RH) to observe changes in the membrane degradation rate.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Characterization\u003c/h2\u003e \u003cp\u003eIn this experiment, all characterization analyses were conducted under cell conditions of 70\u0026deg;C and 100% RH. I-V curve was measured under atmospheric pressure, supplying H\u003csub\u003e2\u003c/sub\u003e and air to the anode and cathode with stoichiometries of 1.5 and 2.0, respectively. CV and LSV were conducted using potentiostat (SI 1287, Solatron, Germany). During CV and LSV measurements, hydrogen and argon were supplied to the anode and cathode of the cell, respectively. CV measurements were conducted for 15 cycles at a scan rate of 30 mV/s in the potential range of 0.05\u0026thinsp;~\u0026thinsp;1.2 V. The electrochemical surface area (ECSA) was calculated using the current density from the 0-0.4 V hydrogen desorption region as the area above the trend line in the 0.4 V electric double layer region. LSV was conducted to observe the change of HCCD and short resistance (SR). HCCD was represented by the current density value at 0.3 V, obtained by sweeping the potential at a scan rate of 1 mV/s over the range of 0 to 0.5 V. SR was calculated as the reciprocal of the slope between voltage and current density from 0.4 to 0.5 V, while by sweeping at a scan rate of 0.5 mV/s over the range of 0.3 to 0.5 V.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Fluoride emission rate\u003c/h2\u003e \u003cp\u003eThe FER was measured quantitatively using the Ion Selective Electrode Meter (PH-250L, ISTEK, Korea). The calibration curve was prepared with a sodium fluoride 1000\u0026thinsp;\u0026minus;\u0026thinsp;100 ppm standard solution. The condensate was collected by condensing the gas coming out of the cell outlet.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results and discussion","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003e3.1 Electrochemical degradation of MEA\u003c/h2\u003e\n \u003cp\u003eOCV holding was conducted to degrade the electrolyte membrane electrochemically (Fig.\u0026nbsp;1). During OCV holding, the cell voltage decreases with time. The decreasing voltage can be divided into reversible voltage decrease, which recovers after activation, and irreversible voltage decrease, which does not recover after activation [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e]. During the OCV holding 48 h, the decreased voltage mostly recovered after activation and characterization, indicating that mostly reversible degradation occurred in the early stages of degradation. However, starting from OCV holding 96 h, some irreversible degradation began to appear, where the decreased voltage did not fully recover. As the durability test progressed, the voltage decreases due to irreversible degradation increased gradually, and at OCV holding for 192 h, the cell voltage decreased to 0.896 V.\u003c/p\u003e\n \u003cp\u003eFigure\u0026nbsp;2 shows the change in FER during OCV holding durability evaluation. FER indicates the variation of fluoride ions emitted from the membrane by electrochemical degradation during OCV holding. Therefore, the change in FER reflects the irreversible degradation of the membrane. The FER consistently increases, reaching 0.0287 \u0026micro;mol/hr cm\u003csup\u003e2\u003c/sup\u003e at OCV holding 192 h. It shows that the irreversible degradation rate gradually increases as the durability test progresses.\u003c/p\u003e\n \u003cp\u003eThe electrochemical degradation of membrane occurs due to radicals formed during the process of hydrogen or oxygen permeating through the membrane and undergoing oxygen reduction reaction (ORR) on the catalyst surface [\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e]. Therefore, the increase in FER during the durability test is related to the radical generation rate. 1) When the membrane thickness decreases due to electrochemical degradation and gas permeability increases, the rate of radical generation increases. However, in this case, the HCCD is constant until OCV holding 144 h (Fig.\u0026nbsp;3b). 2) The high voltage during OCV holding can lead to electrode catalyst degradation, causing ECSA decrease, and platinum dissolution and deposition inside the membrane. Pt deposited in the membrane can accelerate the electrochemical degradation by generating radicals within the membrane [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e]. Figure 4 shows the change of CV and ECSA during OCV holding. The ECSA decreases steadily during the durability test. The high voltages formed during OCV holding can lead to catalyst degradation in the MEA. Therefore, it is speculated that the increasing irreversible membrane degradation rate over time is likely due to catalyst degradation occurring during OCV holding.\u003c/p\u003e\n \u003cp\u003eFigure\u0026nbsp;3b shows HCCD changes during durability test. The HCCD variation serves as an indicator of membrane degradation. As the membrane undergoes electrochemical degradation, its thickness decreases, resulting in an increase in HCCD [\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e]. During OCV holding 144 h, there were no significant changes in HCCD, but after 192 h, the HCCD increased by approximately 30.4% to 2.23 mA/cm\u003csup\u003e2\u003c/sup\u003e. Therefore, the result shows that the membrane was irreversibly deteriorated after OCV holding 192 h.\u003c/p\u003e\n \u003cp\u003eFigure 3c shows the variation in SR during the durability test, demonstrating a steady decline. The decrease in SR is influenced not only by the thinning of the membrane but also by electrode degradation. High voltage of OCV can cause Pt catalyst dissolution, leading to Pt deposition into the membrane. Platinum deposited inside the membrane creates paths for electron flow, thereby reducing SR. These results indicate that the MEA experienced irreversible degradation of both the membrane and electrodes during OCV holding.\u003c/p\u003e\n \u003cp\u003eFigure\u0026nbsp;5 shows the I-V curves of the MEA during OCV holding. The OCV of the MEA decreased from an initial 0.950 V to 0.929 V after the OCV holding 192 h. The OCV is mainly influenced by HCCD and SR. Hydrogen crossover from the anode to the cathode forms a mixed potential at the cathode, thereby decreasing the cell voltage. When the SR decreases, parasitic current increases, resulting in a decrease in cell voltage. In this case, the SR remains above 1 kΩ・cm\u003csup\u003e2\u003c/sup\u003e until OCV holding 192 h (Fig. 3c). Therefore, the increase of HCCD is the main cause of OCV reduction. Furthermore, the current density at 0.6 V decreased from 1264.4 mA/cm\u003csup\u003e2\u003c/sup\u003e to 1077.9 mA/cm\u003csup\u003e2\u003c/sup\u003e after OCV holding 192 h. The decrease in MEA performance is attributed to catalyst degradation. Consequently, we confirmed that the MEA had undergone sufficient irreversible degradation through changes in LSV and OCV. After OCV holding 192 h, we studied operation conditions that could mitigate the degradation rate of the degraded MEA.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003e3.2 Mitigating degradation by controlling humidity and temperature in degraded MEA\u003c/h2\u003e\n \u003cp\u003eAs humidity decreases, the polymer electrolyte membrane of PEMFCs becomes susceptible to the degradation of sulfonic acid groups [\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e]. One way to reduce the degradation rate of the membrane is to increase the humidity of the cell during degradation. Therefore, we conducted the OCV holding at 60% RH, which is higher compared to 30% RH. After the increasing humidity, the rate of OCV decrease accelerated to 2.3 mV/h [Fig.\u0026nbsp;6]. Additionally, FER showed a rapid increase [Fig.\u0026nbsp;7]. The increase in the degradation rate was also clearly evident in changes in HCCD and SR. HCCD increased to 5.76 mA/cm\u003csup\u003e2\u003c/sup\u003e after increasing humidity during OCV holding, and SR decreased to 0.465 kΩ\u0026middot;cm\u003csup\u003e2\u003c/sup\u003e. These results show that increasing the cell humidity in a degraded MEA significantly accelerates the rate of irreversible membrane degradation.\u003c/p\u003e\n \u003cp\u003eGenerally, increasing RH mitigates the membrane degradation by radicals. However, the increase in moisture within the membrane leads to a higher dissolution and diffusion rate of hydrogen through water [\u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e], which can increase the rate of radical formation and accelerate membrane degradation. Therefore, it is speculated that the increase in the rate of radical formation is the cause of the increase in the rate of irreversible degradation. The changes in permeability of the degraded MEA depending on RH are discussed in section \u003cspan class=\"InternalRef\"\u003e3.3\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eAfter OCV holding 240 h, we reduced the cell temperature from 90\u0026deg;C to 60\u0026deg;C to conduct OCV holding and observed changes in degradation rate. Following the cell temperature reduction, the FER during OCV holding sharply decreased to 0.0030 \u0026micro;mol/hr cm\u003csup\u003e2\u003c/sup\u003e. Additionally, the increases in HCCD and decreases in SR were less pronounced compared to when humidity was increased (Fig.\u0026nbsp;8). This reduction in degradation rate can be attributed to the decrease in radical generation rate and reaction rate as the cell temperature decreases. The degradation of the polymer membrane can be considered as a two-step process involving radical generation reaction and polymer degradation reaction caused by radicals. Both reactions can be expressed by the general Arrhenius equation [\u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e]. Thus, the phenomenon of a sharp decrease in membrane degradation rate with decreasing temperature can be explained by the exponential decrease in reaction rate as temperature decreases.\u003c/p\u003e\n \u003cp\u003eAfter OCV holding 268 h, a durability test was conducted by reducing the humidity from 60\u0026ndash;30% at 60\u0026deg;C to observe the degradation rate at low temperature and low humidity. The overall deterioration mitigation effect was less pronounced after reducing the humidity compared to lowering the temperature. Nevertheless, the degradation mitigation effect due to humidity reduction was still significant. The FER at 60\u0026deg;C with 30% RH decreased even further compared to that at 60\u0026deg;C with 60% RH, indicating a further reduction in degradation rate (Fig. 7). Furthermore, the increase in HCCD and the decrease in SR were also reduced. Reduced humidity makes the polymer membrane more susceptible to radical attacks, but in degraded MEAs, humidity reduction repeatedly mitigated the membrane degradation rate. These results suggest that in degraded MEAs, the stage of radical formation may have a greater impact on membrane degradation than the stage where radicals attack the membrane in the two-stage process of polymer membrane degradation.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003e3.3 Changes in HCCD with varying humidity in degraded MEA\u003c/h2\u003e\n \u003cp\u003eIn degraded MEA, increased humidity accelerated the rate of irreversible membrane degradation. This result appears to be due to the increased gas crossover in the MEA under higher humidity. To confirm this, the changes in hydrogen permeability of the MEA before and after degradation were measured as a function of humidity. Since degraded MEAs are susceptible to mechanical stress induced by humidity changes, we used a reinforced MEA with dimensional stability. The reinforced MEA was electrochemically degraded in the same way by applying OCV holding (Fig.\u0026nbsp;9). The HCCD of the reinforced MEA increase from 1.02 to 8.42 mA/cm\u003csup\u003e2\u003c/sup\u003e during OCV holding 144 h.\u003c/p\u003e\n \u003cp\u003eThe changes in HCCD with humidity before and after the degradation of the reinforced MEA are shown in Fig. 10. When the RH was raised from 20\u0026ndash;60%, the HCCD increased from 1.04 mA/cm\u0026sup2; to 1.35 mA/cm\u0026sup2; in the MEA before degradation and from 5.04 mA/cm\u0026sup2; to 6.73 mA/cm\u0026sup2; in the MEA after degradation (Fig. 10). The HCCD of MEAs before and after degradation increased approximately 30% with rising cell humidity. However, the absolute value of the increased HCCD was about five times higher in the degraded MEA. This result shows that the HCCD of degraded MEA is more sensitive to changes in humidity. Therefore, as mentioned in section \u003cspan class=\"InternalRef\"\u003e3.2\u003c/span\u003e, the increased membrane degradation rate with higher humidity in the degraded MEA is interpreted to be due to the increased HCCD.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eIn this study, we investigated the temperature and humidity conditions that mitigate the membrane degradation rate in electrochemically degraded MEAs. The MEA was degraded by performing OCV holding for 192 h, after which we observed changes in degradation rates by varying the temperature and humidity. When the cell humidity was increased from 30% RH to 60% RH, a rapid increase in FER, HCCD, and SR was observed. Although an increase in RH reduces membrane degradation caused by radicals, in degraded MEAs, the rise in RH led to higher hydrogen permeability, which in turn elevated the rate of radical generation, ultimately resulting in an accelerated membrane degradation rate. Durability test conducted at 60\u0026deg;C, 60% RH by lowering the cell temperature showed a decrease in OCV decay rate and FER. Additionally, the rates of HCCD increase and SR decrease were also reduced. This result indicates that temperature reduction led to a decrease in degradation rate caused by radicals. Subsequently, conducting durability evaluation at 60\u0026deg;C and 30% RH by lowering both temperature and humidity resulted in the lowest membrane degradation rate observed. Ultimately, it was confirmed that reducing temperature and humidity, which can decrease radical formation rate, is effective in mitigating membrane degradation in electrochemically degraded MEAs.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eACKNOWLEDGEMENTS\u003c/h2\u003e \u003cp\u003eThis work was supported by the Technology Innovation Program (20011633) funded By the Ministry of Trade, Industry \u0026amp; Energy (MOTIE, Korea).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDOE U.S. DOE fuel cell technologies office multi-year research, development, and demonstration plan. 3.4 fuel cells (2016), \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.energy.gov/sites/default/files/2017/05/f34/\u003c/span\u003e\u003cspan address=\"https://www.energy.gov/sites/default/files/2017/05/f34/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e fcto_myrdd_ fuel_ cells. pdf. 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Protsailo, Journal of The Electrochemical Society, 155 (2007) B50.\u003c/span\u003e\u003c/li\u003e\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":"korean-journal-of-chemical-engineering","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"kjce","sideBox":"Learn more about [Korean Journal of Chemical Engineering](http://link.springer.com/journal/11814)","snPcode":"11814","submissionUrl":"https://www.editorialmanager.com/kjce/default2.aspx","title":"Korean Journal of Chemical Engineering","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Subscription","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"PEMFC, electrochemical degradation, mitigating degradation, hydrogen crossover","lastPublishedDoi":"10.21203/rs.3.rs-4648374/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4648374/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePolymer electrolyte membrane fuel cells (PEMFCs) have faced challenges in achieve their lifespan goals due to the degradation of the membrane electrode assembly (MEA) during long-term operation. To enhance the durability of PEMFCs, it is necessary to research materials that can improve the durability of the membrane and electrodes, as well as to study operating conditions that can reduce degradation. This paper investigated methods to mitigate the membrane degradation of electrochemically degraded MEAs by controlling humidity and temperature among the operating conditions. MEA was degraded electrochemically by conducting open circuit voltage (OCV) holding, and then the degradation rate according to temperature and humidity changes was observed through fluoride emission rate (FER) change. In a degraded MEA, it is shown that increasing cell humidity accelerates membrane degradation. According to linear sweep voltammetry (LSV) results, this was confirmed to be due to the increase in hydrogen permeability caused by the higher humidity. The decrease in temperature lowered the rate of membrane degradation, which is attributed to a decrease in the rate of radical attack and generation resulting from the temperature decrease. Therefore, it was confirmed that to mitigate membrane degradation in electrochemically degraded MEAs, it is effective to reduce temperature and humidity, thereby decreasing the rate of radical formation.\u003c/p\u003e","manuscriptTitle":"Study on Mitigating Membrane Degradation in Degraded Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cell through Temperature and Humidity Control","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-25 15:16:13","doi":"10.21203/rs.3.rs-4648374/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revisions Needed","date":"2024-08-07T02:54:07+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-07-07T05:13:47+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-07-03T03:08:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-07-01T07:12:25+00:00","index":"","fulltext":""},{"type":"submitted","content":"Korean Journal of Chemical Engineering","date":"2024-06-27T08:00:05+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"korean-journal-of-chemical-engineering","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"kjce","sideBox":"Learn more about [Korean Journal of Chemical Engineering](http://link.springer.com/journal/11814)","snPcode":"11814","submissionUrl":"https://www.editorialmanager.com/kjce/default2.aspx","title":"Korean Journal of Chemical Engineering","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Subscription","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"8ab3c3a6-e751-48b4-aa88-6944b572e350","owner":[],"postedDate":"July 25th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-12-02T16:04:16+00:00","versionOfRecord":{"articleIdentity":"rs-4648374","link":"https://doi.org/10.1007/s11814-024-00322-y","journal":{"identity":"korean-journal-of-chemical-engineering","isVorOnly":false,"title":"Korean Journal of Chemical Engineering"},"publishedOn":"2024-11-25 15:58:03","publishedOnDateReadable":"November 25th, 2024"},"versionCreatedAt":"2024-07-25 15:16:13","video":"","vorDoi":"10.1007/s11814-024-00322-y","vorDoiUrl":"https://doi.org/10.1007/s11814-024-00322-y","workflowStages":[]},"version":"v1","identity":"rs-4648374","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4648374","identity":"rs-4648374","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}