Unveiling the role of C60-supported vanadium single atoms for catalytic overall water splitting
Mengyang Li, Tao Yang, Joost M. Bakker, Ewald Janssens, Gao‐Lei Hou
Abstract
Designing efficient bifunctional catalysts that can catalyze overall water splitting to generate hydrogen—an attractive, environmentally friendly and renewable energy carrier—is tremendously important to combat the global warming and energy crisis. Here, we report an atomistic-level understanding of the overall water splitting mechanism, 2H2O → 2H2 + O2, mediated by C60-supported vanadium single atoms. Detailed reaction pathways are calculated, and key intermediates with nominal chemical formulas of C60V+(H2O)2 and C60V+O2 are characterized by infrared spectroscopy. When mediated by an isolated V+, the overall water splitting reaction stops due to geometric restrictions with end product V+(OH)2 or V+O(H2O), whereas it can proceed to complete a catalytic cycle in the presence of the C60-support. Our analyses reveal that the vanadium center undergoes several formal oxidation state changes resulting from the unique electron donating/accepting ability of the C60-support, acting as an “electron sponge,” additional to its role in facilitating the hydrogen transfer.