Basal Plane Activation of SnS2 Thin-film by Fluorine Doping for Selective Solar-driven CO2 Reduction With Enhanced Quantum Efficiency, Advanced Science13, 21(2026)
Tadios Tesfaye Mamo, Mohammad Qorbani*, Adane Gebresilassie Hailemariam, Putikam Raghunath, Che-Men Chu, Wen-Hsin Yuan, Amr Sabbah, Yen-Yu Wang, Shuo-Yun Chang, Ming-Chang Lin, Wei-Yen Woon, Yu-Jung Lu, Heng-Liang Wu*, Ken-Tsung Wong, Kuei-Hsien Chen*, Li-Chyong Chen*
2026/08/19
Photocatalytic conversion of CO2 into value-added fuels offers a viable approach to combat climate change and address global energy demands. Here, we present a fluorine-doped SnS2 thin film with sulfur vacancy (i.e., SV-SnS2:F), prepared via thermal evaporation, post-sulfurization, and fluorine ion-implantation. Substitution of sulfur with fluorine and sulfur vacancy formation changes the product selectivity from CH4 to CO with about 40-fold enhanced yield and boosted internal quantum efficiency (IQE) of 0.52%. Transient absorption, in situ near-ambient pressure X-ray photoelectron, and in situ Fourier transform infrared spectroscopies, along with first-principles density functional theory calculations, suggest that nearest-neighbor Sn to F serves as an active site and stabilizes the *COOH intermediate. Our findings shed light on how F doping activates the nearby elements and its crucial role in intermediate stabilization toward selectivity change in a heterogeneous photocatalysis process.