High-yield production of few-layer boron nanosheets for efficient electrocatalytic N2 reduction.

We report ambient electrochemical N2 fixation at low overpotentials by using two-dimensional (2D) β-boron. The metal-free catalyst afforded both an excellent NH3 yield rate and faradaic efficiency, approximately two times higher than those of bulk boron. We found that several binding sites, especially those involving icosahedral boron in the 2D material, can indeed catalyze N2 reduction efficiently with strong N2 adsorption, thus benefiting initial activation.