Photocatalytic Properties of the g-C 3 N 4 /{010} facets BiVO 4 Interface Z-Scheme Photocatalysts Induced by BiVO 4 Surface Heterojunction

Abstract The g-C 3 N 4 / {010} facets BiVO 4 interface Z-scheme photocatalysts is fabricated by ultrasonic dispersion method. The density functional theory (DFT) shows that the differences of the energy levels in the conduction bands and the valence bands between the {010} and {110} facets of BiVO 4 is about 0.37 and 0.31 V (vs. NHE, pH = 7), respectively. Therefore, the co-exposed {010} and {110} facets of BiVO 4 can form surface heterojunction, which promotes the {010} facets of BiVO 4 with negative charge. The zeta potential indicates that layered g-C 3 N 4 with positive charge. The Raman, FT-IR and XPS analysis demonstrates that the layered g-C 3 N 4 is anchored on the {010} facets of BiVO 4 through strong interface electrostatic interaction, which leads to form a built-in electric field at the contact interface. Under the built-in electric field driving, photogenerated electrons in the CB of {010} facets of BiVO 4 rapidly recombines with the holes in the VB of g-C 3 N 4 to form the interface Z-scheme heterostructure. That is, BiVO 4 surface heterojunction ultimately induces the formation of interface Z-scheme heterostructure. The interface Z-scheme heterostructure not only facilitates the space separation of the photogenerated carriers, but also accumulates electrons in the more negative potentiated CB of g-C 3 N 4 and holes in the more positive VB of {110} facets of BiVO 4 . Consequently, by means of the I-t, LSV and EIS measurements, the g-C 3 N 4 /{010} facets of BiVO 4 interface Z-scheme photocatalysts presents extraordinary photoelectrochemical performance. More importantly, the degradation rate of g-C 3 N 4 /{010} facets of BiVO 4 interface Z-scheme photocatalysts can reach the highest 88.3% within 30 min under visible light irradiation, and the mineralization ability (96.03%) is about 2.24 and 3.32 times as high as that of BiVO 4 (42.83%) and g-C 3 N 4 (28.89%), respectively.