Ambient NH3 synthesis via electrochemical reduction of N2 over cubic sub-micron SnO2 particles
Electrochemical N2-to-NH3 fixation under ambient conditions is emerging as a promising alternative to the energy-intensive and CO2-emitting Haber–Bosch process. However, this process involves difficulty in N2 activation, underlining the demand of electrocatalysts for the N2 reduction reaction (NRR). In this work, cubic sub-micron SnO2 particles on carbon cloth (SnO2/CC) are proposed as an efficient NRR electrocatalyst for ambient N2 conversion to NH3 with excellent selectivity. Electrochemical tests reveal that SnO2/CC attains a large NH3 yield of 1.47 × 10−10 mol s−1 cm−2 at −0.8 V vs. reversible hydrogen electrode (RHE) and a high Faradaic efficiency of 2.17% at −0.7 V vs. RHE in 0.1 M Na2SO4, outperforming most reported aqueous-based NRR electrocatalysts. Notably, it also shows strong electrochemical stability.