Accelerated N₂ reduction kinetics in hybrid interfaces of NbTiO₄ and nitrogen-doped carbon nanorod via synergistic electronic coupling effect

Electrochemical ammonia synthesis through the atmospheric nitrogen reduction reaction (NRR) is a promising method for sustainable fertilizer and carbon-free hydrogen energy carriers. The inevitable selectivity gap against hydrogen evolution reaction and inert nitrogen (N₂) hinders the device-level usage of nitrogen cathodes. In this work, we report engineered electrocatalyst/support interface of NbTiO₄ nanoparticles supported on nitrogen-doped carbon nanorods (NbTiO₄@NCNR) to catalyze NRR. Insisted by the pitfalls to rationally design N₂ reduction catalysts, the strong catalyst-support interaction strategy is adapted to tune the selectivity towards NRR. Electrochemical tests reveal that NbTiO₄@NCNR hybrid accelerates a 10-fold increase in N₂ selectivity compared to pure metal oxide. Using first-principles calculations, we identify the underlying mechanism of enhanced performance: bridging bonds in the interface as electron transport channels to promote the N₂ reduction kinetics. Essentially, this study provides an insight into how to overcome the immense kinetic barrier of NRR using smartly engineered interfaces of hybrid materials.