Engineering Dual Oxygen Simultaneously Modified Boron Nitride for Boosting Adsorptive Desulfurization of Fuel

Abstract

Oxygen atoms usually co-exist in the lattice of hexagonal boron nitride (h-BN). The understanding of interactions between the oxygen atoms and the adsorbate, however, is still ambiguous on improving adsorptive desulfurization performance. Herein, simultaneously oxygen atom-scale interior substitution and edge hydroxylation in BN structure were constructed via a polymer-based synthetic strategy. Experimental results indicated that the dual oxygen modified BN (BN–2O) exhibited an impressively increased adsorptive capacity about 12% higher than that of the edge hydroxylated BN (BN–OH) fabricated via a traditional method. The dibenzothiophene (DBT) was investigated to undergo multi-molecular layer type coverage on the BN–2O uneven surface via π–π interaction, which was enhanced by the increased oxygen doping at the edges of BN–2O. The density functional theory calculations also unveiled that the oxygen atoms confined in BN interior structure could polarize the adsorbate, thereby resulting in a dipole interaction between the adsorbate and BN–2O. This effect endowed BN–2O with the ability to selectively adsorb DBT from the aromatic-rich fuel, thereafter leading to an impressive prospect for the adsorptive desulfurization performance of the fuel. The adsorptive result was in good accordance with Freundlich and pseudo-second-order adsorption kinetics model results. Therefore, the designing of a polymer-based strategy could be also extended to other heteroatom doping systems to enhance adsorptive performance.

Keywords

• Polymer-based synthetic strategy
• Interior substitution BN
• Oxygen doping
• Adsorptive desulfurization