Constructing a novel p-n heterojunction photocatalyst LaFeO 3 /g-C 3 N 4 with enhanced visible-light-driven photocatalytic activity

Abstract

Abstract An n-type g-C 3 N 4 modified with p-type LaFeO 3 , was fabricated to from a novel LaFeO 3 /g-C 3 N 4 p-n heterostructure for the highly effective photocatalytic degradation of RhB. The photocatalytic activity of LaFeO 3 /g-C 3 N 4 was 19.1 times higher than that of pristine LaFeO 3 under visible light irradiation, and LaFeO 3 /g-C 3 N 4 heterojunction retained excellent stability after four recycles. The improved photocatalytic performance of LaFeO 3 /g-C 3 N 4 heterostructure can be assigned to the enhanced absorption in the visible light region and low recombination rate of the electron-hole pairs, which was confirmed by the results of photocurrent, EIS and OCP. Moreover, based on the p-n heterojunction between LaFeO 3 and g-C 3 N 4 , the photocatalytic mechanism of the LaFeO 3 /g-C 3 N 4 hybrid was discussed and the possible electrons/holes transfer and separation process was also proposed. This study shows a novel p-n heterojunction structure that could provide a scientific basis for the design of efficient photocatalysts.