Interfacial engineering of molybdenum disulfide by vanadium-MXene for efficient electrochemical nitrate reduction

Electrochemical nitrate reduction reaction (NITRR) has emerged as a promising approach for both nitrate contamination removal and ammonia producing in mild ambient conditions. Herein, a novel strategy based on interfacial engineering is proposed to improve the catalytic performance of MoS₂ via introducing few-layer V₂C MXene heterostructure. This explicitly tailored method effectively addresses the challenge of MoS₂ aggregation, while simultaneously inducing transformative changes in the native electron orbitals of Mo active sites in MoS₂. The optimal heterostructure MoS₂@V₂C catalyst emerges with excellent attributes: nitrate removal rate (93%), ammonia selectivity (84%), and Faradic efficiency (80%) at −0.9 V (vs. reversible hydrogen electrode (RHE)) in a low NO₃⁻ concentration. The theoretical research demonstrates the energy barrier of *NO to *NOH is significantly reduced by 0.92 eV after inducing V₂C MXene. Moreover, there is an evident shift in the center of the d-band towards the Fermi level, accompanied by a potent suppression of the hydrogen evolution reaction.