Highly Efficient Adsorption of Oils and Pollutants by Porous Ultrathin Oxygen-Modified BCN Nanosheets

The effective removal of oils and pollutants by adsorption plays a crucial role in the water purification and treatment process. Various nanostructured adsorbents have been reported in the past, while a majority of these lack in some critical chemical and structural characteristics which limit their practical applications. To enhance the adsorption process, there is a need for the development of advanced adsorbents with excellent adsorption capacity. Herein, porous ultrathin, recyclable, and large-scale oxygen -modified borocarbonitride (O-BCN) nanosheets with the large specific surface area and high temperature oxidation resistance have been synthesized, which possess a remarkable adsorption performance for different oils ranging from 2360 to 4370 wt %. In the case of crude oil, it showed the maximum adsorption capacity equal to 43.7 times its own weight. Moreover, the saturation adsorption for Rhodamine B (RhB) dye reached 300.8 mg/g which denotes more than 98% removal efficiency. Kinetics studies reveal the pseudo-second-order model which follows the Freundlich isotherm suggesting multilayer heterogeneous adsorption on the surface of the ultrathin O-BCN nanosheets. This novel ultrathin O-BCN material is a low-cost, highly efficient, and ecofriendly alternative to expensive, inefficient, and toxic chemicals used for wastewater treatment.