Pd‐Doped Co<sub>3</sub>O<sub>4</sub> Nanoarray for Efficient Eight‐Electron Nitrate Electrocatalytic Reduction to Ammonia Synthesis
Xiaoya Fan, Chaozhen Liu, Zixiao Li, Zhengwei Cai, Ling Ouyang, Zerong Li, Xun He, Yongsong Luo, Dongdong Zheng, Shengjun Sun, Yan Wang, Binwu Ying, Qian Liu, Asmaa Farouk, Mohamed S. Hamdy, Feng Gong, Xuping Sun, Xuping Sun, Yinyuan Zheng
Abstract
Abstract Ammonia (NH 3 ) is an indispensable feedstock for fertilizer production and one of the most ideal green hydrogen rich fuel. Electrochemical nitrate (NO 3 − ) reduction reaction (NO 3 − RR) is being explored as a promising strategy for green to synthesize industrial‐scale NH 3 , which has nonetheless involved complex multi‐reaction process. This work presents a Pd‐doped Co 3 O 4 nanoarray on titanium mesh (Pd‐Co 3 O 4 /TM) electrode for highly efficient and selective electrocatalytic NO 3 − RR to NH 3 at low onset potential. The well‐designed Pd‐Co 3 O 4 /TM delivers a large NH 3 yield of 745.6 µmol h −1 cm −2 and an extremely high Faradaic efficiency (FE) of 98.7% at −0.3 V with strong stability. These calculations further indicate that the doping Co 3 O 4 with Pd improves the adsorption characteristic of Pd‐Co 3 O 4 and optimizes the free energies for intermediates, thereby facilitating the kinetics of the reaction. Furthermore, assembling this catalyst in a Zn‐NO 3 − battery realizes a power density of 3.9 mW cm −2 and an excellent FE of 98.8% for NH 3 .