High-Throughput computational screening of Single-atom embedded in defective BN nanotube for electrocatalytic nitrogen fixation

Abstract

The boron nitride nanotubes (BNNTs) have been widely used in various energy applications such as hydrogen storage, gas sensor, carbon dioxide reduction reaction, and so on. Herein, the potential application of BNNT-based catalysts was explored in electrocatalytic nitrogen reduction reaction (eNRR) by density functional theory (DFT) computations. A series of single metal/non-metal atoms (18 transition metals (3d ∼ 5d) and 6 non-metals (B, C, N, Si, P, and As)) supported on the defective BNNT were investigated. Among them, Os-doped (Os@BNNT) single-atom catalyst (SAC) can significantly promote the NRR process, and possess a rather low overpotential (0.31 V), as well as high selectivity over HER competition. The confined Os atom not only serves as an electron donor to supply electrons for NRR, but also acts as a channel for interfacial charge transfer between substrate and NRR intermediates. Moreover, the curved surface of BNNT can decrease the barrier for protonating *NH2 to·NH3. The synergistic collaboration of single-atom Os catalyst and curved surface of BNNT facilitates the NRR process. Our findings open up a new avenue for designing novel nanotube-based materials as eNRR electrocatalysts.