Local Enhanced Electric Field Assisted Electrocatalytic Nitrate Reduction to Ammonia Using Ni(TCNQ) ₂ /NF Nanostructures

Abstract Environmentally sustainable electrocatalytic nitrate reduction (NO ₃ RR) is a very promising method for the synthesis of ammonia at room temperature via the complex eight‐electron/nine‐proton transfer mechanism. Herein, the local electric field‐assisted electrochemical NO ₃ RR process is proposed to identify the origin of catalytic activity and charge transfer kinetics resulting from different morphologies of the electrocatalyst. Accordingly, Ni(TCNQ) ₂ /NF nanorods (NRs) and nanotips (NTs) are fabricated on Ni foam as electrocatalysts for the NO ₃ RR. The Ni(TCNQ) ₂ /NF NTs exhibits an impressive ammonia yield of up to 11286.9 µg h ⁻¹ cm ^{− 2} and a Faradaic efficiency (FE) of 83.7% at −1.0 V versus RHE, representing nearly a 2.2‐fold increase in yield compared to the Ni(TCNQ) ₂ /NF NRs. This greater performance is attributed to the local enhanced electric field (LEEF) generated at the tip‐like Ni(TCNQ) ₂ /NF NTs. Furthermore, a Zn–NO ₃ ⁻ battery is developed here, and Ni(TCNQ) ₂ /NF NTs shows a maximum power density of 2.15 mW cm ⁻² . Experimental and computational findings demonstrate that the geometric and electrical properties of the nanostructures' shape significantly influence the electrochemical NO ₃ RR by enhancing the kinetics of charge transfer. This study seeks to advance research on morphology‐dependent electrochemical NO ₃ RR through the strategic control of local electric field intensity in electrocatalysts.