Fabrication of Carbon‐Doped BiOCl Nanosheets With High {001} Facet Exposure for Photocatalytic Ciprofloxacin Oxidation and Cr(VI) Reduction

Antibiotics and heavy metals are increasingly polluting water systems, and photocatalysis is a promising method to remove these pollutants. This article prepared carbon‐doped BiOCl nanosheets with high {001} facet exposure via hydrothermal method using glucose as carbon source, which can remove ciprofloxacin (CIP) and Cr(VI) individually or simultaneously. When precursor glucose content increases, nanosheet thickness decreases while {001} facet exposure still stays at a high level of 78%. The synergy of carbon doping, reduced thickness, and high {001} exposure improves the visible light absorption efficiency, narrows the bandgap, and enhances the separation and migration efficiency of carriers. As a result, the material has much higher photocatalytic activity than pure BiOCl in both photooxidation and photoreduction of pollutants. The optimized C‐7‐BiOCl sample with Bi ³⁺ /glucose molar ratio 5:7 has 173% higher CIP oxidation efficiency and 230% higher Cr(VI) reduction efficiency than pure BiOCl. It also has excellent simultaneous removal efficiency for CIP and Cr(VI) in mixed pollutants, and its photocatalytic activity is 3.80 times and 4.64 times higher than that in single‐pollutant system, respectively. This study provides a simple preparation method for C‐doped BiOCl with improved photooxidation and photoreduction activity, and it is expected to be used in actual wastewater treatment.