First-principles calculations on performance of the g-C3N4/LNS-TiO2(Cr+C) heterojunction photocatalyst in water splitting process

Abstract

In this paper, the photocatalytic ability of the g-C3N4/LNS-TiO2(Cr + C) heterostructure in water splitting process is studied theoretically. Calculations indicate that this heterojunction is a stable structure. The PDOS results show that the CBM and VBM for this heterojunction come from different components. Charge transfer analysis indicates that when the two materials are joined together to form heterojunction, electrons in g-C3N4 will flow into LNS-TiO2(Cr + C), thus creating a built-in electric field from g-C3N4 to LNS-TiO2(Cr + C). Research on band edge positions and photocatalytic mechanism indicates that this heterostructure is Z-scheme photocatalyst, in which the powerful photogenerated electrons (0.86 eV higher than the H2 producing level) and holes (2.46 eV lower than the O2 producing level) are preserved in different constitutes to participate in photocatalytic reactions. In general, this study enriches the photocatalyst types for water splitting process.