Electrocatalytic N2-to-NH3 conversion using oxygen-doped graphene: experimental and theoretical studies†
Abstract
Oxygen-doped graphene (O–G) derived from sodium gluconate is identified as a promising candidate to effectively catalyze ambient electrohydrogenation of N2 to NH3. Electrochemical tests on O–G in 0.1 M HCl suggest a large NH3 yield of 21.3 μg h−1 mgcat.−1 and a high faradaic efficiency of 12.6% at −0.55 and –0.45 V vs. reversible hydrogen electrode, respectively, with strong electrochemical and structural stability in 0.1 M HCl. Density functional theory calculations reveal the NRR catalytic mechanism and suggest that both the CO and O–CO groups contribute more greatly to the NRR compared with the C–O group.