Synergistic Electrocatalytic Nitrogen Reduction Enabled by Confinement of Nanosized Au Particles onto a...

A N₂ fixation by the electrocatalytic nitrogen reduction reaction from humidified air is regarded to be a critical tool for producing NH₃ and reducing the globally accelerating CO₂ emissions. Notwithstanding great efforts to improve catalyst activity and selectivity, promoting catalyst accessibility to high N₂ concentrations to ensure that active sites fulfill their function should be a promising design direction. Here, Au nanoparticles are firmly anchored through atomic O on the surface of two-dimensional Ti₃C₂ using an ultrasound reduction process. Akin to the conspicuous role of the web in the predatory process of spiders, N₂ adsorption experiments primarily suggest that a Ti₃C₂ "web" is beneficial for extraction of N₂ from air, and embedding high valence-state Au clusters in the Ti₃C₂ "web" strengthens the chemical bonding effect toward N₂ molecules. The high energy of N₂ adsorption on the interface between gold clusters and Ti₃C₂ is the driving force for weakening triple N≡N bonds, and thereby the activation energy barrier is lowered via effective stabilization of N2H* species and destabilizing NH2NH2* under an alternative pathway. With Au loading content of ∼0.94%, Au/Ti₃C₂ exhibits an outstanding average yield of 30.06 μg h^-1 mg^-1 for NH₃ production, with a high Faraday efficiency of 18.34% at -0.2 V.