Charge transfer optimization: Role of Cu-graphdiyne/NiCoMoO4 S-scheme heterojunction and Ohmic junction

Abstract

The effective separation ability of photogenerated carriers plays a crucial role in catalytic hydrogen production. Establishing a heterojunction structure is an effective means to overcome the limited carrier separation ability of some single catalysts. In this paper, Cu, graphdiyne (GDY) and NiCoMoO₄ are successfully coupled to construct a composite photocatalyst NCY-15%. The addition of sheet GDY effectively prevents the aggregation of NiCoMoO₄, increases the number of active sites, and enhances the light-trapping ability of the composite catalyst. The synergistic interaction of S-scheme heterojunction and Ohmic junction heterojunction between Cu, GDY and NiCoMoO₄ provides a unique transfer pathway for electrons, facilitating the rapid separation of photogenerated carriers and accelerating electron transfer, while retaining electrons with strong reducing capacity to participate in hydrogen production, thereby increasing the hydrogen evolution rate. This provides a new way for the development of GDY based photocatalysts.