Boron doped with carbon nitride with high specific surface area exhibits excellent capacity for adsorption of Cr(III)

Abstract

Cr(III) has attracted considerable attention due to its toxicity and its potential to oxidize into Cr(VI). Boron-doped carbon nitride (BCN) was synthesized, resulting in material with remarkable thermal stability and radiation resistance, specifically designed for adsorption of Cr(III). Characterization and batch experiments indicated BCN2 possesses a considerably large specific surface area and numerous active sites, contributing to its impressive adsorption capacity for Cr(III) at pH 5, which exceeds 1200 mg/g. Kinetic and isotherm studies were investigated and revealed the system follows pseudo-second-order kinetics and fit best with the Freundlich isotherm at high concentrations. Notably, Statistical physics models revealed a notably higher density of the material’s adsorption sites. Density functional theory was employed to calculate three structures of BCN combined with Cr(III). Interestingly, the reducing ability of adsorbent for Cr(VI) was explored, offering valuable insights for designing environmentally friendly materials.