BiOCl microspheres with controllable oxygen vacancies: Synthesis and their enhanced photocatalytic performance

The BiOCl microspheres consisted of nanosheets were synthesized at room temperature. It is demonstrated that the concentration of oxygen vacancies (OVs) in BiOCl can be controllable by modulating H+ concentration. The as-prepared BiOCl were further utilized in photocatalytic degradation of Rhodamine B (RhB) and Ciprofloxacin (CIP). Benefiting from the oxygen vacancies, BiOCl with rich OVs exhibited a superior photocatalytic activity than poor-BiOCl with few OVs prepared without addition of HNO3. Furthermore, of the obtained BiOCl microspheres, the BiOCl with 13.6% OVs showed the best photocatalytic property. And the rate constant for degradation of RhB and CIP were 0.834 min−1 and 0.018min−1, which are 1.7 and 1.6 times than poor-BiOCl. It is indicated that the optimized OVs concentration could capture photo-generated electrons most efficiently, which could improve the carrier migration rate. This work elevated the photocatalytic performance of BiOCl without the need for additional compound, which opens up a new avenues for design of highly efficient catalyst.