Template-Free Synthesis of Oxygen-Doped Bundlelike Porous Boron Nitride for Highly Efficient Removal of Heavy Metals from Wastewater

Heavy metal pollution has raised global concerns with regards to environmental sustainability, thus demanding the development of high-performance adsorbent materials. Herein, we report a novel solvent-mediated synthetic strategy for preparing oxygen-doped bundlelike porous boron nitride (OBPBN) through a simple two-step template-free reaction that involves thermal evaporation of the solvent and high-temperature pyrolysis processes. The resulting OBPBN with an interconnected mesoporous microstructure exhibits excellent adsorption performance for various heavy metal ions including Cu2+, Pb2+, Zn2+, and Cr3+. In particular, the exceptional selectivity for the extraction of Cu2+ (427.12 mg/g) and Pb2+ (316.32 mg/g) places the as-obtained OBPBN among the top boron nitride-based adsorbent materials. The high adsorption performance for heavy metals is mainly attributed to the synergistic effect of oxidizing groups and lattice defects induced by oxygen doping as well as the high specific surface area (474.3 m(2)/g) and porosity (0.332 cm(3)/g) originating from the OBPBN. In addition, the excellent reusability of the OBPBN has been also confirmed. The current synthetic approach would lead to a facile and high throughput fabrication of porous boron nitride materials for future applications in environment remediation, such as the extraction of heavy metals from waste and polluted water.