One-step synthesis of Bi2O2CO3/Bi2S3 S-scheme heterostructure with enhanced photoactivity towards dibutyl phthalate degradation under visible light

Bi 2 O 2 CO 3 /Bi 2 S 3 heterojunction was prepared by one-step hydrothermal method, where Bi(NO 3 ) 3 was employed as Bi source, Na 2 S was used as a sulfur source, and CO(NH 2 ) 2 was adopted as C source. The load of Bi 2 S 3 was adjusted by changing the content of Na 2 S. The prepared Bi 2 O 2 CO 3 /Bi 2 S 3 illustrated strong photocatalytic activity towards dibutyl phthalate (DBP) degradation. The degradation rate was 73.6% under the irradiation of visible light for 3 h, which were 3.5 and 1.87 times for Bi 2 O 2 CO 3 and Bi 2 S 3 , respectively. In addition, the mechanism for the enhanced photoactivity was investigated. After combined with Bi 2 S 3 , the formed heterojunction structure inhibited the recombination of photogenerated electron-hole pair, improved the visible light adsorption, and accelerated the migration rate of the photogenerated electron. As a result, analysis of the radical formation and the energy band structure revealed that Bi 2 O 2 CO 3 /Bi 2 S 3 was consistent with the S-scheme heterojunction model. The S-scheme heterojunction allowed the Bi 2 O 2 CO 3 /Bi 2 S 3 to possess high photocatalytic activity. The prepared photocatalyst presented acceptable cycle application stability. This work not only develops a facile one-step synthesis technique for Bi 2 O 2 CO 3 /Bi 2 S 3 , and also provides a good platform for the degradation of DBP.