In Situ X-ray Photoelectron Spectroscopy (XPS) Demonstrated Graphdiyne (g-CnH2n-2) Based GDY-CuI/NiV-LDH Double S-Scheme Heterojunction for Efficient Photocatalytic Hydrogen Evolution

As a new two-dimensional layered carbon material, graphdiyne (GDY) is widely used in various fields because of its excellent electrical conductivity and tunable electronic structure. In this work, graphdiyne, a two-dimensional layered carbon material, is prepared by an alkyl terminal coupling method using Cu+ as a catalyst. Nickel-vanadium hydro calcite (NiV-LDH) is anchored on the surface of GDY-CuI bya solvothermal method to form a double S-scheme heterojunction photocatalytic hydrogen precipitation system. The double S-scheme heterojunction suppressed the electron-hole recombi-nation in the composite catalyst, which greatly improved the transfer rate of photogenerated carriers. Meanwhile, a tight and unique interface is formed in the composite, which not only accelerates the separation and transfer of electron holes but also improves the catalytic stability of the composite. H2 (73.65 smol) is produced in 5 h in triethanolamine solution, which is 4.1 and 3.7 times higher than those with NiV-LDH and NiV-LDH/CuI. Twenty-five hour cycling experiments demonstrated the catalytic stability of the materials. This work provides an effective strategy for the rational construction and application of graphdiyne group hetero structures in the field of photocatalytic hydrogen evolution.

Automated summary

Graphdiyne (GDY) is prepared using Cu+ as a catalyst and anchored with nickel-vanadium hydro calcite (NiV-LDH) to form a double S-scheme heterojunction photocatalytic hydrogen precipitation system. This heterojunction improves the transfer rate of photogenerated carriers and the catalytic stability of the composite. The production of H2 in triethanolamine solution is significantly higher compared to NiV-LDH and NiV-LDH/CuI. This work provides an effective strategy for the rational construction and application of graphdiyne group heterostructures in the field of photocatalytic hydrogen evolution.