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

Abstract

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 N₂ 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.