Accessing polyanionic redox in high voltage Li-rich thiophosphate-type materials

Accessing polyanionic redox in high voltage Li-rich thiophosphate-type materials | 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 Article Accessing polyanionic redox in high voltage Li-rich thiophosphate-type materials M Saiful Islam, Pezhman Zarabadi-Poor, Jungwoo Lim, Xuefei Wang, and 12 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2605439/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract In the search for novel positive electrode materials for lithium-ion cells, Li-rich sulfides are attracting increasing interest. Despite the success of polyoxyanion-based cathodes such as LiFePO4, their thiophosphate counterparts have remained poorly understood. Here, we investigate Li2FeP2S6, a Li-rich thiophosphate-type material that exhibits the highest known voltage (3 V) for a sulfide electrode in a solid-state configuration. Through isostructural transition-metal substitutions, we identify a Mn-substituted compound, Li2Fe0.8Mn0.2P2S6, with higher capacity than the parent Fe system while maintaining high voltage. Hard X-ray photoelectron spectroscopy and ab initio molecular dynamics simulations indicate that Mn substitution increases capacity beyond the formal transition-metal redox limit by activating P2S6 polyanionic redox, involving interlayer S–S bond formation with no evidence of Fe or Mn cation migration. This demonstration of polyanionic redox in a thiophosphate-type material highlights the opportunity to explore alternative Li-rich thiophosphate structures as high-capacity lithium-ion cathodes. Physical sciences/Materials science/Materials for energy and catalysis/Batteries Scientific community and society/Energy and society/Energy efficiency Full Text Additional Declarations There is NO Competing Interest. Supplementary Files ThioNChemSuppInfo27Sept25.pdf Accessing polyanionic redox in high-voltage Li-rich thiophosphate-type materials Cite Share Download PDF Status: Posted Version 1 posted 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. 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