A strong metal-support interaction strategy for enhanced binder-free electrocatalytic nitrate reduction

An electrocatalytic nitrate reduction reaction (NO3RR) is an attractive strategy to maintain the nitrogen neutral. Fe nanoparticles (Fe NPs) are among the most promising electrocatalysts for the NO3RR with low cost and high performance. However, the durability of Fe-based catalysts is poor owing to the aggregation and oxidation of iron. Herein, a series of self-supported Fe/support catalysts has been synthesized by a simple hydrothermal and in situ thermal reduction strategy, exhibiting strong metal-support interaction (SMSI) between Fe active sites and supports. Remarkably, the iron nanoparticles loaded on graphite felt (Fe/GF) exhibited an optimal electrochemical NO3RR performance with NO3- conversion of 67.7% and N-2 selectivity of 96.6%, which is attributed to the enhanced dispersity and conductivity. This study not only provides a universal method for SMSI composite catalysts but also lays the foundation for their large-scale application.