Carbon doped hexagonal boron nitride nanoribbon as efficient metal-free electrochemical nitrogen reduction catalyst

Abstract The electro-catalytic nitrogen reduction reaction (NRR) to produce ammonia is a significant and challenging mission in chemistry, in which metal-free NRR catalysts with high activity, stability and selectivity are still highly desired. Here, we have systematically investigated the properties of pristine and carbon doped hexagonal boron nitride nanoribbons (BNNRs) for efficient nitrogen capture and reduction. Our results suggest that BNNRs exhibit excellent N2 capture abilities, which are demonstrated to be originated from the edge lone pair electrons. Then we highlight that doping carbon can significantly enhance the NRR catalytic performance of BNNRs by reducing the NRR reaction overpotential from 1.14 to 0.39 V. Further analysis unravels that doping C can selectively modulate the adsorption free energy of NRR intermediates without influencing the excellent activation ability of pristine BNNRs, which has been confirmed to arise from the charge redistribution of edge boron atoms. Our findings pave the way of h-BN for N2 capture and pioneer the application of carbon doped BNNR as a novel NRR catalyst.