Effect of Interface Contact Between C and C3N4 on Photocatalytic Water Splitting

The contact form of the heterojunction interface has an importance effect on interfacial photoelectron transfer and photocatalytic property. Here, C/C 3 N 4 heterojunction with three types of interface contact between C and C 3 N 4 have been constructed, including C/C 3 N 4 -I, C/C 3 N 4 -HI, C/C 3 N 4 -D. The physico-chemical properties of the prepared catalysts were characterized by TEM, XRD, XPS, Raman, FT-IR, UV–VIS DRS and UPS. The results indicate that the interface composition (Cg/Cs, Nt/Ns) and valence band characteristic of the photocatalysts are strongly dependent on the interface contact form of C and C 3 N 4 . Compared with the C/C 3 N 4 -HI and C/C 3 N 4 -D, the sample C/C 3 N 4 -I present higher ratios of Cg/Cs and Nt/Ns, stronger light response and appropriate band locations. These findings reveal that the C deposited on the surface of C 3 N 4 promotes the efficiencies of light harvest and charge carrier separation, ultimately resulting in an enhanced photocatalytic performance for pure water splitting. Graphical Abstract