MOF-derived B, N co-doped porous carbons as metal-free catalysts for highly efficient nitro aromatics reduction

A convenient and rational route is designed to synthesize B, N co-doped porous carbon materials (BNPCs) via a two-step calcination method derived from adenine-based bio-MOF-1. By using the adenine from bio-MOF-1 precursor as the endogenous N source and boric acid as the exogenous B source, the N and B elements are uniformly doped in metal-free BNPCs. B has lower electronegativity than C, leading to a higher positive charge density and the enhanced activation of C atoms. Owing to the synergistic effect between B and N, the co-doped catalysts not only increase electrical conductivity of catalysts to improve electron transfer , but also produce more additional active sites to intensify the catalytic performance for the reduction of 4-NP. The as-synthesized carbon materials have abundant mesopores , graphite structure, dual heteroatoms doping and thus excellent catalytic performances. In particular, BNPC-1000, obtained by pyrolysis at 1000 °C, shows superior catalytic efficiency of 95.2% and high catalytic cycling stability for the 4-NP reduction.