Cu–Bi Bimetallic Sulfides Loaded on Two-Dimensional Ti3C2Tx MXene for Efficient Electrocatalytic Nitrogen Reduction under Ambient Conditions

In this paper, Ti3C2Tx MXene/Cu–Bi bimetallic sulfide (Ti3C2Tx/BiCuS2.5) composites were prepared by a simple in situ deposition method for electrocatalytic nitrogen reduction reaction (eNRR). Compared to Ti3C2Tx/Bi2S3 and Ti3C2Tx/CuS, the eNRR performance of Ti3C2Tx/BiCuS2.5 is significantly improved. The results show that Ti3C2Tx/BiCuS2.5 exhibits a NH3 yield of 62.57 μg h–1 mg–1cat. in 0.1 M Na2SO4 at −0.6 V vs reversible hydrogen electrode, and the Faradaic efficiency (FE) reaches 67.69%, which is better than that of Ti3C2Tx/CuS (NH3 yield: 52.26 μg h–1 mg–1cat., FE: 34.15%) and Ti3C2Tx/Bi2S3 (NH3 yield: 54.04 μg h–1 mg–1cat., FE: 37.38%). According to density functional theory calculations, the eNRR at the Ti3C2Tx/BiCuS2.5 surface is the alternating pathway. The 1H NMR experiment of 15N proves that the N of NH3 generated in the experiment originates from N2 passed during the experiment.