In situ irradiated XPS proved efficient charge transfer on graphdiyne (CnH2n-2) based tandem NiFe PBA/CuI/GD S-scheme heterostructure for photocatalytic hydrogen production

Due to its abundant carbon chemical bonds, large conjugated system and natural pore structure, graphdiyne (GD, CnH2n-2) shows great advantages in growth, assembly and performance regulation, and is a key material to promote innovative development in catalysis, energy and other fields. In this study, NiFe PBA cube was prepared by coprecipitate method, and then NiFe PBA/CuI/GD ternary composite photocatalyst was formed by tightly coating NiFe PBA and CuI with graphitylene material. In situ irradiated X-ray photoelectron spectroscopy characterizes the change in electron cloud density of a catalyst under illumination, so as to determine the series-type transfer path of photogenerated electrons between three single photocatalysts, thus revealing the formation of double S-scheme heterojunction. Photocurrent and fluorescence tests have confirmed that the photogenerated carriers in NiFe PBA/CuI/GD can be transferred rapidly and utilized efficiently to participate in the photo-catalytic reaction under the action of strong interfacial electric field. In addition, the three-dimensional structure of NiFe PBA and CuI and the surface carbon layer synergistic effect to expand the utilization rate of visible light catalyst. This work provides a new idea for the construction of S-scheme heterojunction and the application of new carbon materials in the field of photocatalysis.