One‐step Mechanical Synthesis of Oxygen‐defect Modified Ultrathin Bi12O17Br2 Nanosheets for Boosting Photocatalytic Activity

Abstract Benefiting from high contact specific surface area and interface defects, ultrathin two‐dimensional (2D) defect‐rich catalysts have attracted widespread attention in the photocatalytic field. However, the traditional synthetic methods are complicated to operate and prone to acid‐base pollution, which are counter to the high‐efficiency and environmental protection concepts of the present age. Herein, novel rich oxygen vacancies (OVs) ultrathin Bi 12 O 17 Br 2 nanosheets were prepared via one‐step mechanical ball milling with high‐energy grinding, which can enhance the specific surface area, reduce the thickness and boost the escape of more surface oxygen atoms for the Bi 12 O 17 Br 2 catalyst. The ultrathin structure with rich OVs are beneficial to the introduction of more active sites and the separation and migration of photogenerated carriers. Under visible light illumination, the Bi 12 O 17 Br 2 ultrathin nanosheets exhibit excellent photodegradation ability of antibiotic, which is 23∼48 times relative to bulk Bi 12 O 17 Br 2 . Hence, this study designs an efficient and convenient approach to fabricate bismuth‐rich materials with surface OVs, which is conducive to large‐scale industrial production.