Physicochemical Characteristics of Nitrogen Sorption on High-Porous Powders of Graphene-Like Boron Nitride

Abstract

The porous structure of graphene-like boron nitride t-BN_g powders is evaluated. The material is homogenous, micro-mesoporous, with a distribution of slit-like pores in the range 3.53–4.12 nm corresponding to 55% of the volume and 60% of the specific surface area of mesoporous. The specific surface area of micropores calculated with the Dubinin–Kadlets method (t-method) is 28.3 m²/g and the specific surface area of mesopores calculated with the Barrett–Joyner–Halenda method is 141 m²/g. Powders of nanosized t-BN_g synthesized from urea contain impurities of polycondensed flat particles of boron oxonitride. Impurities as refined sublimate (white powder) are separated out of the washed and dried t-BN_g powder by subsequent vacuum heat treatment at 540 K and a pressure to ≤1.0 Pa. The sublimate is identified as heterocyclic six-membered dimer with molecular formula H(OH)[(BON)₂](OH)H.