One pot synthesis of ultrathin boron nitridenanosheet-supported nanoscale zerovalent iron for rapid debromination of polybrominated diphenyl ethers

Abstract

To minimize the aggregation and size effects of nanoscale zerovalent iron (nZVI), nZVI/boron nitride nanosheets (BNNSs) composites were fabricated via a one pot “autoclave route” on a gram-scale. BNNSs (1–6 nm) supported nZVI (4–40 nm) was prepared by heating NaBH₄, FeCl₃ and NaN₃ at 400 °C. The BNNSs matrixes benefit the retention of the activity for nZVI. The high specific surface area (182 m² g⁻¹) and density of structural defects allows enrichment of the pollutants, leading to a relatively high conversion by the nearby supported nZVI. Meanwhile, the gram-scale bifunctional nZVI/BNNSs have both reductive and magnetic properties, which make them highly reactive towards the test polybromodiphenyl ethers (PBDEs) and also easy to separate. The reaction rate of nZVI/BNNSs is almost twice that of the nZVI made in our lab. This study indicates that gram-scale nZVI/BNNSs are highly efficient and effective materials that can be utilized to treat PBDEs-contaminated sites, followed by the sequential magnetic separation.