Preparation of rose-like Bi2O2CO3 photocatalyst with enhanced performance for photocatalytic degradation of mineral flotation wastewater

Abstract

Eight kinds of bismuth oxycarbonate (Bi2O2CO3, BOC) with different microscopic morphology were prepared to study the influence of microscopic morphology on its photocatalytic performance. The crystal structure and microscopic morphology of Bi2O2CO3 were regulated by different synthetic recipes and routes. The SEM and TEM show the samples can be classified into two-dimensional (2D) and three-dimensional (3D) Bi2O2CO3 materials. The BOC-8 possesses a rose-like structure and a specific surface area (SBET) of 44.93 m2/g. In the experiments of degrading mineral flotation agent sodium isobutyl xanthate (SIBX). The photocatalytic performance of 3D samples is generally superior to that of 2D samples, and BOC-8 exhibits the best photocatalytic performance. After 90 min of simulated sunlight irradiation, the degradation ratio of SIBX over BOC-8 is 92.41 %. The transient photocurrent-time curves, electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) spectra show that BOC-8 has excellent photogenerated electron and hole separation efficiency. The degradation pathway of SIBX was explored. And the hydroxyl radicals (OH) is the main active oxygen species for SIBX degrading. The enhanced photocatalytic degradation performance of BOC-8 samples originated from the increase of SBET, improved light utilization and more efficient photogenerated charge separation caused by the formation of 3D structure.