Sustainable Fluorinated Silicon Dielectric Design for Enhanced Contact‐Electro‐Chemistry

Abstract

Abstract Solid–liquid contact electrification (CE) has recently emerged as a powerful means of initiating interfacial chemical reactions via charge transfer. Fluorinated ethylene propylene (FEP) and polytetrafluoroethylene (PTFE) are frequently employed as solid dielectrics owing to their fluorine‐rich surfaces, which exhibit strong electron‐withdrawing characteristics. However, their high environmental cost and poor surface modifiability hinder the broader adoption of contact‐electro‐chemistry (CE‐Chemistry). Here, we report a low‐cost and tunable dielectric alternative based on silicon powder, surface‐functionalized with fluorinated alkyl chains to mimic the interfacial properties of conventional fluoropolymers. Fluorinated silicon powders (F‐Si) were synthesized via a mild self‐assembly approach using 1H,1H,2H,2H‐perfluorodecyltriethoxysilane. The resulting F‐Si powders exhibited a 30‐fold enhancement in methyl orange degradation efficiency compared to unmodified silicon, and a 4‐fold improvement in phenol degradation relative to size‐matched FEP powder. In contrast, aggressive fluorination via piranha‐assisted pretreatment (P‐F‐Si) induced particle aggregation and loss of CE reactivity, highlighting the importance of controlled surface engineering. Furthermore, CE‐Chemistry enabled the first noble‐metal‐free oxidation of I − to I 3 − , establishing a low‐energy, cost‐effective paradigm for catalytic iodine conversion. Together, these advances provide a sustainable materials design framework for CE‐Chemistry, with broad implications for scalable, green chemical transformation technologies.