Porous hexagonal boron nitride whiskers fabricated at low temperature for effective removal of organic pollutants from water

Abstract Developing advanced adsorbent materials for effective removal of dyes from water is of critical importance for environmental and water source protection. Hexagonal boron nitride (h-BN) whiskers were synthesized at low temperature, i.e. 1173 K in nitrogen/hydrogen (5% hydrogen) via polymeric precursor method. The obtained h-BN whiskers possessing high surface area of 964.4 m 2 /g exhibit good adsorption performance for rhodamine-B (RhB) and methyl blue (MB) with the maximum adsorption capacities reaching 210.1 mg/g and 13973.0 mg/g, respectively. They also exhibit valuable adsorption performance for sulfamethoxazole (SMX) with an adsorption rate of 33% at room temperature. The saturated material could be regenerated by simply heating in air and still maintain a high removal rate of >80% even after 10 cycles. From thermodynamic viewpoint, the adsorption process of RhB on BN whiskers is physisorption, exothermic and spontaneous. In addition, high density defects, micro/mesopore in the structure and the noncovalent interaction such as π–π stacking interaction between lamellar BN whiskers and aromatic rings also give an important contribution to the adsorption capacity.