Experimental and first‐principles investigations on g‐C ₃ N ₄ /ZnS heterostructures with enhanced photocatalyst capability

Abstract

g‐C3N4 was employed as a modified substance for modification engineering of wurtzite‐ZnS photocatalysts to overcome its limited light response and stability. The g‐C3N4/ZnS (CNZS) photocatalyst was synthesized by solvothermal reaction of g‐C3N4, thiourea and zinc acetate. The results show that wurtzite‐ZnS spheres were loaded on the surface of g‐C3N4 with well uniformed size. The photocatalytic activity of the catalyst was determined by the degradation of MB and Rh.B under visible light. The degradation rates of Rh.B and MB by CNZS were 96% and 97%, much better than that of pure ZnS. The addition of g‐C3N4 promoted the visible light response of wurtzite‐ZnS and inhibited the recombination of photogenerated electrons with holes. The density functional theory (DFT) results indicated that the components of both valence band and conductive band were changed for the CNZS system. Compared to pure ZnS, the band gap of CNZS was decreased about 0.5 eV, and the work function calculations were in good agreement with the experimental results. As a result, the heterostructure of CNZS made it beneficial to the electron transfer from g‐C3N4(2p of N) to ZnS (3p of S) and absorption edge has been extended to about 600 nm.