Palladium-Modified MoS₂ with Accelerated Water Hydrolysis for Highly Efficient Electrocatalytic Ammonia Production

Electrocatalytic nitrogen reduction reaction (NRR) under environmental conditions is an environmentally friendly way. However, the first hydrogenation step in the reaction process limits the kinetic process. Herein, we report the synthesis of MS–Pdx (x = 0.5, 1.0, 1.5) catalysts for electrocatalytic nitrogen reduction by rapid Joule heating preparation of S vacancy-containing MoS2 with vacancy-induced anchoring of Pd in an Ar/H2 atmosphere. MS–Pd1 nanosheets exhibit high activity and selectivity at room temperature, with an NH3 yield of ∼96.41 μg h–1 mg–1cat. at −0.50 V vs RHE and a Faradaic efficiency of 39.38% at −0.40 V vs RHE. Density-functional theory (DFT) calculations manifested that the unique activity of MS–Pd1 stemmed from the effective enhancement of nitrogen adsorption by Mo near its S vacancies and the effective promotion of H2O dissociation by MoS2 after the introduction of Pd, that the generated *H combined with *N2 instead of generating H2, and that the effective combination of the two reduced the free-energy barriers for the hydrotropic conversion of *N2 to *NNH. This study provides new ideas for the design of N2 electroreduction catalysts and strengthens the understanding of N2 activation over MoS2-based catalysts.