Selective Electroreduction of Dinitrogen to Ammonia on Molecular Iron Phthalocyanine /O-MWCNT Catalyst under Ambient Conditions
Effective catalysts with sufficient activity and selectivity are essential for NRR. Plenty fruitful NRR electrocatalysts have been investigated with regard to NH3 production under ambient condition in recnt years. However, well-defined and modifiable molecular catalysts have rarely been reported for NRR to date. Here, molecular FePc was grafted on O-MWCNT surface as NRR electrocatalyst to improve its recyclability. This catalyst displayed high electrocatalytic ability and selectivity, giving a large NH3 yield of 36 µg h−1 mg−1cat., a FE of 9.73% and a TON of 12.56 after 2 h electrocatalytic reaction in an acidic electrolyte, superior to most of reported materials. DFT calculations indicated that the NRR preferentially proceed along the alternating pathway, the activation of N2 to produce N2H* is the rate-limiting step with a ΔG value of 1.79 eV. Conclusively, we reports FePc/O-MWCNT as a low-cost, high-efficiency NRR catalyst that also offers a valuable reference for molecular electrocatalyst research in electrochemical nitrogen reduction.