Engineering of Band Structure of Bismuth Selenide Ultrathin Nanosheets as Multifunctional Material for Photocatalytic Application

Abstract N‐substituted bismuth selenide (BSN) material is synthesized by a one‐step solvothermal route and used for the photocatalytic application. As‐prepared BSN consists of ultrathin nanosheets and has a quasi hexagonal morphology. The results show the superior performance of BSN‐2 for degradation of multi‐pollutants and the ciprofloxacin and phenol removal rates reach 88.8 and 83.6%, respectively, under irradiation of simulated solar for 2 h, which is much higher than those over pristine bismuth selenide. The significant improvement of photocatalytic performance is attributed to ultrathin nanosheets structure and N introduction that contribute to the inhibition of photoelectron‐hole pair recombination and the enhancement of light absorption. The possible mechanism is proposed based on characterization and theoretical calculation of the energy band structure. The results indicate that BSN‐2 is a high‐efficient photocatalyst for the removal of multi‐organic pollutants in wastewater and this research provides a simple strategy for reasonable design and synthesis of Bi‐based materials for environmental remediation.