A recyclable photocatalytic tea-bag-like device model based on ultrathin Bi/C/BiOX (X = Cl, Br) nanosheets

[Display omitted] •Ultrathin BiOX (X = Cl, Br) nanosheets decorated with Bi and C are prepared.•Bi/C/BiOX nanosheets show excellent adsorptive and photocatalytic activity.•A recyclable photocatalytic tea-bag-like device model is proposed and fabricated.•The devices with Bi/C/BiOX photocatalysts exhibit considerable performance. Photocatalysis is considered as a promising method to solve the global water contamination crisis. However, the recycle of powdery photocatalysts is difficult to achieve, which limits their practical application. In this work, a recyclable photocatalytic tea-bag-like device model is proposed for the first time as far as we know, and applied in wastewater treatment. Meanwhile, a novel and efficient photocatalyst, the ultrathin BiOX (X = Cl, Br) nanosheets decorated with metal Bi, carbon and oxygen vacancy (Bi/C/BiOX), is prepared by a facile hydrolysis method. The decoration of Bi, carbon and oxygen vacancy vastly improve the optical response in visible region. Further, the introduction of oxygen vacancy level, surface plasmon resonance (SPR) effect of Bi and outstanding electronic conductivity of carbon synergistically accelerate the charge separation of BiOX. Moreover, the ultrathin nanosheet structure equips Bi/C/BiOX with tremendous specific surface area and abundant active sites. Thus, the Bi/C/BiOX photocatalysts exhibit excellent adsorption capacity and photocatalytic activity for the degradation of antibiotic tetracycline hydrochloride and rhodamine B. More importantly, a considerable photocatalytic performance of the tea-bag-like device model with Bi/C/BiOX is observed and there is no leakage of photocatalysts during the photocatalytic test, demonstrating its great potential for practical application in wastewater treatment. Therefore, this work not only provides a new perspective to design efficient photocatalysts, but also offers a novel strategy for photocatalysts recycling.