Construction of active site involving zinc coupled with nitrogen and phosphorus on the eucalyptus bark derived porous carbon for the enhancement of N2O adsorption: Experiments and mechanism

Abstract

Recently, the warming effect of nitrous oxide (N₂O) in the atmospheric has shown an accelerating upward trend. Adsorption techniques from biomass porous carbon with low energy consumption may control N₂O emissions. This study obtained a series of eucalyptus bark-derived biomass porous carbons through co-doping modification with different ratios of ZnCl₂ (Zn source), urea (N source), and H₃PO₄ (P source). Combining characterization, experiments, and theory calculations, it has been concluded that the N₂O adsorption capacity of porous carbon is significantly enhanced by the co-doping of Zn, N, and P modifications, and that as-prepared porous carbon also exhibits excellent regenerative adsorption performance. Among them, the sample of BC800–1.5/1/2 displayed a prominent adsorption capacity of 1.86 mmol g⁻¹, with the S_BET and the pore volume being 700.912 m²·g⁻¹ and 0.284 cm³ g⁻¹, respectively. Moreover, the addition of Zn co-doping leads to a variation of the chemical functional groups on the porous carbon, which then gives rise to the novel C-Zn bonds that contribute significantly through chemisorption, thereby enhancing the N₂O adsorption capacity of the triple-co-doped eucalyptus bark-based porous carbon. The presented findings provide a scientific strategy for the highly efficient adsorption of N₂O by co-doped eucalyptus bark-based porous carbon preparations.