A new concept: Volume photocatalysis for efficient H2 generation __ Using low polymeric carbon nitride as an example.

A new concept of volume photocatalysis of of solid catalysts is created, and an efficient reaction system constructed using low polymeric carbon nitride as a photocatalyst and biomass-derived formic acid as a reactant. The apparent quantum yield for photocatalytic hydrogen evolution reaches 51.9% at 400 nm in formic acid reaction system. • It is the first time to propose the concept of volume photocatalysis of solid catalysts. • Low polymeric carbon nitride (PCN) can act as a volume photocatalyst. • An efficient PCN photocatalytic H 2 evolution is achieved in formic acid reaction system. • Apparent quantum yield for photocatalytic H 2 generation at 400 nm reaches 51.9%. • This work provides a new strategy to enhance photocatalytic reaction efficiency. Conversion of solar energy into H 2 via photocatalytic reforming of biomass or its derivatives is an attractive technology. However, the photocatalytic reaction efficiency is usually low due to the high recombination of photogenerated electrons and holes. Herein, we demonstrate a new concept and strategy of volume photocatalysis of solid catalysts and construct an efficient reaction system using low polymeric carbon nitride (PCN) as a volume photocatalyst and biomass-derived formic acid as a reactant. In this system, PCN allows the reactant to enter its bulk and in-situ scavenge photogenerated holes, which greatly inhibits the recombination of the electrons and holes. As a result, the left electrons can effectively migrate from the bulk to the surface of PCN to reduce protons/water molecules into hydrogen. The apparent quantum yield (AQY) for photocatalytic hydrogen evolution reaches 51.9% at 400 nm in formic acid reaction system. These findings provide new insights for understanding heterogeneous photocatalysis. [ABSTRACT FROM AUTHOR]