0D/2D heterojunction constructed by Ag₂S quantum dots anchored on graphdiyne (g-C_nH_2n-2) nanosheets for wide spectrum...

Precisely crafting heterojunctions for efficient charge separation is a major obstacle in the realm of photocatalytic hydrogen evolution. A 0D/2D heterojunction was successfully fabricated by anchoring Ag₂S quantum dots (Ag₂S QDs) onto graphdiyne (GDY) nanosheets (Ag₂S QDs/GDY) using a straightforward physical mixing technique. This unique structure allows for excellent contact between GDY and Ag₂S QDs, thereby enhancing the rate of charge transfer. The light absorption capabilities of Ag₂S QDs/GDY extend up to 1200 nm, enabling strong absorption of light, including infrared. Through DFT calculations and in-situ XPS analysis, it was demonstrated that incorporating Ag₂S QDs onto GDY effectively modulates the electronic structure, promotes an internal electric field, and facilitates directional electron transfer. This directed electron transfer enhances the utilization of electrons by GDY and Ag₂S QDs, with the added benefit of Ag₂S QDs serving as electron reservoirs for efficient photocatalytic hydrogen evolution. A 7 %Ag₂S QDs/GDY composite exhibited impressive efficiency and stable performance in photocatalytic hydrogen evolution (2418 μmol g^-1 h^-1), which is much higher than that of GDY and Ag₂S QDs. This study conclusively demonstrates that the 0D/2D heterojunction formed by GDY and Ag₂S QDs can establish high-quality contact and efficient charge transfer, ultimately enhancing photocatalytic performance.