Green synthesis and DFT insight into carbon-doped ZnO nanoparticles derived from rambutan peel for enhanced photocatalytic performance

Green synthesis and DFT insight into carbon-doped ZnO nanoparticles derived from rambutan peel for enhanced photocatalytic performance | 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 Green synthesis and DFT insight into carbon-doped ZnO nanoparticles derived from rambutan peel for enhanced photocatalytic performance Tran Do Dat, Phan Van Qui, Pham Thanh Cong, Nguyen Thi Ngoc Huyen, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8091837/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract In this study, carbon-doped ZnO nanoparticles (C–ZnO) were synthesized via a dual-functional green route using rambutan (Nephelium lappaceum L.) peel extract as both a natural reducing/stabilizing agent and an in situ carbon source, eliminating the need for external dopants. This biomass-derived strategy enables waste valorization, cost reduction, and controlled carbon incorporation for enhanced photocatalytic activity. Systematic optimization of calcination temperature (400–800 °C) and time (4–8 h) revealed that C–ZnO calcined at 600 °C for 6 h exhibited optimal structural and electronic properties, including moderate carbon content (8.18 wt%) and a narrowed band gap of 3.08 eV. XRD and Raman analyses confirmed the formation of wurtzite ZnO with substitutional/interstitial carbon incorporation and embedded graphitic carbon domains (ID/IG < 1), while FTIR validated Zn–O and carbon-related functional groups. Compared with pristine ZnO photocatalysts reported in the literature, the optimized C–ZnO sample exhibited markedly enhanced photocatalytic performance, achieving up to 99.75% methylene blue degradation under UV irradiation (180 min, pH 11, 10 mg L⁻¹ MB, 50 mg catalyst). Radical scavenging experiments identified •OH and h⁺ as the dominant reactive species, and the catalyst retained over 73% of its activity after five successive cycles. Density functional theory (DFT) calculations revealed that carbon doping introduces C 2p–O 2p hybridized states, narrows the band gap, and promotes charge redistribution within the ZnO lattice, thereby improving charge separation and photocatalytic efficiency. These combined experimental and theoretical results demonstrate that biomass-derived carbon doping is an effective and sustainable strategy for tuning the electronic structure of ZnO toward high-performance photocatalytic environmental remediation. Carbon-doped ZnO Green synthesis Rambutan peel extract Photocatalytic degradation Density functional theory (DFT) Full Text Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 09 Jan, 2026 Reviewers invited by journal 09 Jan, 2026 Editor invited by journal 08 Jan, 2026 Editor assigned by journal 05 Jan, 2026 First submitted to journal 03 Jan, 2026 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-8091837","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":572160644,"identity":"79171555-c180-412f-a265-763197f0c7bb","order_by":0,"name":"Tran Do 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