Fe(TCNQ)₂ nanorod arrays: an efficient electrocatalyst for electrochemical ammonia synthesis via the nitrate reduction reaction

The electrochemical reduction of nitrate to ammonia (NO3RR) catalyzed by metal organic frameworks (MOFs) is a promising and efficient method for reducing nitrate pollution in water while simultaneously producing a valuable product, ammonia. Herein, we report the 3D nanoarray architecture of the metal organic complex Fe-(tetracyanoquinodimethane)(2) Fe(TCNQ)(2) as an efficient electrocatalyst that exhibits a high ammonia yield rate of 11 351.6 mu g h(-1) cm(-2) and faradaic efficiency (FE) of 85.2% at -1.1 V vs. RHE and excellent catalytic stability up to 2 days. The excellent catalytic performance is evaluated by ATR-FTIR spectroscopy and a series of control experiments. Density functional-based theoretical calculations are carried out to identify Fe-N-4 active sites in metal-organic network structures. This study showcases the advancement of transition metal-based organic frameworks as very effective electrocatalysts for the reduction of nitrate to ammonia (NH3).