Preparation of BiOBr/CaCO ₃ Composite with Excellent Photocatalytic Activity and Cycling Stability

BiOBr has excellent visible‐light photocatalytic activity, but its poor cycling stability greatly limits its practical application. To overcome this shortcoming, BiOBr nanosheets were prepared on cuttlebone‐derived CaCO 3 in this work. A porous calcite with a coarse surface was obtained after the cuttlebone was heat‐treated in air. Then BiOBr nanosheets were designed to grow on the surface of the heat‐treated cuttlebone through a hydrothermal method. Compared with the pure BiOBr, the BiOBr/CaCO 3 composite had stronger visible‐light absorption, larger Brunauer–Emmett–Teller surface area, and mesopore volume. The BiOBr/CaCO 3 composite demonstrated enhanced photocatalytic activity over the pure BiOBr, degrading 91.9% of tetracycline hydrochloride within 54 min irradiation, which was 1.49 times higher than that of the pure BiOBr. Additionally, it achieved a 97.26% degradation of rhodamine B within 150 min irradiation, matching the performance of the pure BiOBr. Furthermore, the BiOBr/CaCO 3 composite also exhibited superior cycling stability. This work provides a simple strategy for reducing the cost of photocatalysts.