Ni–Fe Dual‐Site Polymer Catalyst for High Performance and Stable Electrochemical Urea Synthesis from CO2 and NO3 −

TL;DR

This paper introduces a new Ni–Fe catalyst that efficiently converts CO2 and nitrate into urea, offering a sustainable and scalable method for fertilizer production.

Contribution

A novel Ni–Fe dual-site polymer catalyst is developed for stable and high-performance urea synthesis from CO2 and NO3−.

Findings

The Ni–Fe catalyst achieves a urea yield of 449.56 mg h−1 gcat−1 and 41.06% Faradaic efficiency.

Fe incorporation enhances charge transfer and stabilizes reaction intermediates for efficient C–N coupling.

The catalyst maintains over 30% Faradaic efficiency for 30 h, showing strong operational stability.

Abstract

The electrochemical synthesis of urea from nitrate (NO3
−) and carbon dioxide (CO2) presents a sustainable alternative to conventional methods, mitigating pollution and reducing energy consumption. Herein, a rationally designed Ni–Fe bimetallic pyromellitic acid polymer catalyst (Ni‐PMDA@Fe) is developed for efficient urea electrosynthesis. This metal–organic polymer provides structural robustness, abundant active sites, and a tunable coordination environment, optimizing C–N coupling kinetics. Ni‐PMDA@Fe achieves a urea yield of 449.56 mg h−1 gcat
−1 and a Faradaic efficiency (FE) of 41.06% at –0.5 VRHE, significantly surpassing monometallic controls (Ni‐BDC, Ni‐PMDA). Fe incorporation modulates the electronic structure of Ni, enhances charge transfer, and stabilizes key reaction intermediates, enabling synergistic NO3
−/CO2 coupling. Comprehensive characterization confirms homogeneous Fe doping and a dual‐metal‐site configuration. Unlike single‐atom or monometallic systems, the Ni–Fe dual‐site architecture optimally tunes the adsorption kinetics of critical intermediates. The catalyst maintains a FE exceeding 30% over a 30 h stability test, demonstrating robust operational stability. Furthermore, techno‐economic analysis (TEA) indicates competitive production costs when powered by renewable energy, highlighting scalability potential. This word demonstrates a practical pathway for sustainable urea synthesis by converting pollutants (NO3
−/CO2) into value‐added product, thereby contributing to decarbonizing fertilizer production and mitigating nitrogen pollution.

A schematic illustration of the Ni‐PMDA@Fe bimetallic polymer catalyst for electrocatalytic urea synthesis from NO3
‐ and CO2. The Fe‐modulated coordination environment enhances active site dispersion and electron transfer efficiency, enabling efficient C–N coupling. Electrochemical performance data and techno‐economic analysis (TEA) confirm the sustainability and scalability of this green urea production strategy.© 2026 WILEY‐VCH GmbH

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