Theoretical Studies on the Electronic and Optical Properties of Honeycomb BC₃ monolayer: A Promising Candidate for Metal-free Photocatalysts

Abstract

By employing first-principles computations and particle-swarm optimization calculations, we theoretically confirmed the honeycomb geometry of experimentally realized BC₃ sheet, which is constructed by the hexagonal carbon-ring fragments surrounded by six boron atoms and has pronounced thermodynamic stabilities. Remarkably, the computations also demonstrate the visible-light absorption, high carrier mobilities, and promising reduction and oxidation capacities of the BC₃ monolayer, indicating its efficient absorption of solar radiation, fast migration of electron and holes, and excellent capabilities of photoinduced carriers in a photocatalytic process, respectively. Additionally, its indirect band gap, spatially separated charge distributions, and great difference in mobilities of electrons and holes should lead to the restricted recombination of photoactivated e^--h⁺ pairs within BC₃ monolayer. All above-mentioned characteristics suggest that the honeycomb BC₃ monolayer should be a recommendable candidate for metal-free photocatalysts, which is worthy of further verifications and explorations in experimental studies.