Ambient electrochemical N2 reduction to NH3 under alkaline conditions enabled by layered K2Ti4O9 nanobelt

Using electrocatalytic N2 reduction to make NH3 is considered to be an attractive environmentally-friendly alternative to the Haber–Bosch process, which is rather energy-intensive and has heavy CO2 emissions. However, only limited success has been achieved in identifying metal oxides as effective electrocatalysts for the N2 reduction reaction (NRR) under alkaline conditions. In this communication, we report that a K2Ti4O9 nanobelt is able to effectively electrocatalyze the ambient NRR for N2-to-NH3 fixation at alkaline pH. When tested in 0.1 M KOH, a high NH3 yield of 22.88 μg h−1 mg−1cat. and a faradaic efficiency of 5.87% were attained. Moreover, K2Ti4O9 also demonstrates good selectivity and high electrochemical stability for NH3 formation.