Carbon Doping and Nanosheet Architecture Engineered Bismuth Oxychloride with Improved Visible Light Photocatalytic Degradation Activity

Bismuth oxychloride (BiOCl, BOC) emerges as a prospective candidate for environmental remediation due to its distinctive layer structure. However, its photocatalytic degradation activity is hindered by insufficient visible light responsiveness ability and the immanent recombination of photogenerated charges. Herein, carbon-doped BOC nanosheets (C-BOC NS) were prepared through solvothermal treatment utilizing oleylamine and oleic acid in dual roles, which serve as structure-directing agents to inhibit layer stacking for constructing nanosheet architecture while also being carbon sources for lattice doping. The photocatalytic activity was appraised by degrading rhodamine B (RhB) and tetracycline hydrochloride (TH) under visible light illumination. The C-BOC NS exhibit 4.73 and 3.36 times enhancements in degradation rate constants for RhB and TH respectively compared to pristine BOC. In addition, the conceivable mechanism with enhanced photocatalytic degradation activity was analyzed. The results suggest that carbon doping introduces midgap states within the band structure, allowing C-BOC NS to effectively harness visible light. Furthermore, an upshift of conduction band potential favoring oxygen activation is observed under the cooperative effect of carbon doping and nanosheet architecture. Moreover, photoelectrochemical and surface photovoltage results demonstrate the shortened transport distance significantly suppresses carrier recombination. Enabled by these, the production of holes and superoxide radicals derived from oxygen activation is facilitated. The work proposes a simple and effective bifunctional strategy for synchronously optimizing structure properties, offering potential insights into designing efficient BOC-based photocatalytic materials for the degradation of pollutants.