In-situ constructing oxygen-enriched vacancies BiOCl with 3D flower-structure for exceptional visible-light-driven photocatalytic properties

Bismuth oxychloride (BiOCl), emerging as a novel environmentally friendly nanomaterial, possesses considerable potential for photocatalytic degradation of organic wastewater. However, inadequate active sites and inhibited electron separation efficiency severely hinder its visible-light photocatalytic activity. To address this issue, herein we present a facile approach to in-situ construct BiOCl three-dimensional (3D) flower-structure (BOC-F) with oxygen-enriched vacancies for abundant active sites and effective electron separation efficiency through morphology control and vacancy engineering. The visible photocatalytic activity of BOC-F and BiOCl with 2D flaky-structure (BOC-S) was assessed through a systematic examination of the degradation efficiencies of tetracycline hydrochloride (TC-HCl) and rhodamine B (RhB). Under visible light irradiation, BOC-F exhibited superior visible photocatalytic activity, effectively degrading tetracycline hydrochloride (TC-HCl) (20 mg/L) and rhodamine B (RhB) (200 mg/L) within 90 min and 20 min of light exposure, respectively. The findings elucidate that BOC-F, possessing a 3D flower structure, manifests a heightened concentration of oxygen vacancies in contrast to BOC-S, consequently yielding excellent performance. Moreover, The ESR test showed that singlet oxygen (O-1(2)) and hole (h(+)) were two main active species in the photocatalytic degradation of BOC-F. This work not only furnishes a facile method for constructing oxygen-rich vacancies in BiOCl but also provides fresh insights into the potential for enhancing the visible photocatalytic properties of Bi-based materials through vacancy engineering.