Unveiling the Mechanism of Nitrogen Fixation by Single-Atom Catalysts and Dual-Atom Catalysts Anchored on Defective Boron Nitride Nanotubes

Abstract

It is challenging to explore stable and high-efficiency electrocatalysts toward nitrogen reduction reaction (NRR) under ambient conditions. Herein, the catalytic potential of boron nitride nanotubes (BNNTs) embedded with transition-metal (TM) atoms as electrocatalysts for NRR has been systematically studied by the first-principles calculation method. Three single-atom catalysts (SACs), Fe/BNNT, Mn/BNNT, and Pd/BNNT, were selected out from 13 candidate materials TM/BNNT (TM = Fe, Co, Ni, Cu, Zn, Ti, V, Cr, Mn, Mo, Pt, Pd, and Au) by density functional theory (DFT) calculations, and their limiting potentials were −0.65, −0.61, and −0.91 V, respectively. It indicated that they have good catalytic activity for the reduction of N2 to NH3. Meanwhile, to further improve the catalytic activity, two dual-atom catalysts (DACs), FeFe/BNNT and MnMn/BNNT, were constructed, their limiting potentials were −0.17 and −0.58 V, respectively. The results show that FeFe/BNNT and MnMn/BNNT can greatly improve the catalytic performance. Our work provides a new idea for constructing high-efficiency electrocatalysts with BNNT as a new carrier.