In-plane graphene incorporated borocarbonitride: Directional utilization of disorder charge via micro π-conjugated heterointerface for photocatalytic CO2 reduction

Despite the potential of hexagonal boron carbon nitride (h-BCN) with a unique graphite-like structure in the field of photocatalysis, the serious photocarrier recombination caused by disordered charge transfer has limited its practical application. In this work, we propose a conceptual design of in-plane heterostructures consisting of graphene sheet and non-phase-separated borocarbonitride (Gsheet–BCN) with micro π-conjugated heterointerface for directional utilization of disorder charge. The obtained G150–BCN exhibits 10 times longer carrier decay lifetime (16.82 ns) and 3.7 times higher CO yield (51.14 μmol g−1 h−1) than pristine BCN. It was confirmed by systematical characterizations and theoretical calculations that the micro π-conjugated heterointerface enables the directional transport of photo-induced electrons from BCN to graphene domains, resulting in enhanced carrier separation and CO2 reduction efficiency. This work developed a unique synthetic route to the design and construction of heterojunction with proper interface and rational electronic structure for efficient separation of photoexcited charges.