In-situ fabrication of Bi2S3/g-C3N4 heterojunctions with boosted H2 production rate under visible light irradiation
Youmei Li, Feiyang Rao, Junbo Zhong, Jianzhang Li
Abstract
The limited response region of visible light and the fast recombination of photo-induced carriers severely confine the photocatalytic behavior of the original g-C 3 N 4 . In this work, using thioureas and bismuth citrate as precursors, Bi 2 S 3 /g-C 3 N 4 heterojunction photocatalytic materials were successfully in-situ constructed by a one-step solid phase method. Suffering from 4 h visible-light shining, the amount of H 2 evolution over 1.5 wt% Bi 2 S 3 /g-C 3 N 4 heterojunctions has reached 826.2 μmol·g −1 , and the H 2 production rate over Bi 2 S 3 /g-C 3 N 4 heterojunctions achieves 236.1 μmol·g −1 ·h −1 , which is 7 times as high as that of the pure g-C 3 N 4 . Construction of Bi 2 S 3 /g-C 3 N 4 not only adjusts the band structures but also improves the visible light response capacity of g-C 3 N 4 . The rapid transfer of photogenerated charge pairs between Bi 2 S 3 and g-C 3 N 4 interfaces facilitates the separation of photo-excited charge pairs, sequentially boosting the photocatalytic H 2 production rate. Combined with the various characterization and analysis results, the reasonable and possible mechanism for enhancement in the performance of Bi 2 S 3 /g-C 3 N 4 heterojunction photocatalytic materials was proposed. This work offers potential insight into the boosted photocatalytic performance of g-C 3 N 4 for H 2 production exposure to visible light by constructing the heterojunctions to efficiently separate the photo-induced charge pairs.