Mechanically stable structured porous boron nitride with high volumetric adsorption capacity

Abstract

The development of adsorbents into structured and robust forms remains a challenge for emerging porous materials. In the context of porous boron nitride (BN), studies point to a tradeoff between...

Formation Mechanism and Porosity Development in Porous Boron Nitride

“…Hoffendahl et al 21 indicated the formation of carbon nitride from melamine but referred to the reaction of boron oxide with ammonia to eventually form BN. Among all the above studies, only those of Ramirez Leyva et al 15 and Tian et al 17 cover the formation of porous BN, and they link the porosity to gases released during the reaction, as also suggested by our earlier study. 1 A recent study by Hoppe and Gross reports ammonium bis(biureto)borate as an intermediate in boron nitride formation using boric acid and urea under N 2 .…”

“…To ensure the deployment of the material at a larger scale, one must be able to tune its properties for a given application, which clearly necessitates an understanding of its formation process. Few studies investigated the mechanism of porous BN formation via bottom-up synthesis. ,− Most report the formation of hexagonal boron nitride ( h -BN), a noncarbonaceous analogue of graphite with relatively low surface area (typically <200 m 2 g –1 ) and porosity compared to porous BN. , In all the studies of porous BN, a few reactions have been suggested that account for the formation from boron- and nitrogen-containing precursors, but there is no consensus to date for a comprehensive reaction scheme with respect to the thermal treatment. In addition, reported syntheses use different reagents, gas atmospheres, and reaction conditions, which impact the formation process and resulting product.…”

“…The two mechanisms may not be mutually exclusive and may also depend on the synthesis parameter space. Under the former mechanism fall, for instance, the studies by Brožek and Hubáček, Ramirez Leyva et al, Wu et al, Tian et al, and Hoffendahl et al The second category includes the work by Gong et al, who used graphene as a precursor. Hoffendahl et al indicated the formation of carbon nitride from melamine but referred to the reaction of boron oxide with ammonia to eventually form BN.…”

Cu-functionalised porous boron nitride derived from a metal–organic framework

“…The analysis of the core level spectra of B 1s and N 1s confirmed the formation of BN, evidenced by the peaks at ∼190.8 and ∼398.4 eV, respectively. 9 The additional peaks at 192.2 eV on the B 1s spectrum and 399.5 eV on N 1 s spectrum belong to the B–O–N bonds. 9,54 Oxygen is a known and unavoidable impurity of porous BN due to surface oxidation.…”

“…The porosity in BN is linked to the formation and release of Nand C-containing porogens derived from the precursors. 9,52,57 Finally, we investigated the optoelectronic properties of the Cu/BN samples using UV/vis diffuse reectance spectroscopy (UV/vis DRS). The samples displayed two main absorption peaks at $210 and $250 nm, respectively, and these peaks remained almost unchanged upon addition of Cu particles (Fig.…”