摘要
Electrocatalytic nitrate reduction reaction is considered as a promising and sustainable method for ammonia synthesis.However,the selectivity and yield rate of ammonia are limited by the competitive hydrogen evolution reaction and the complex eight-electron transfer process.Herein,we developed a(FeCoNiCu)Ox/CeO_(2)polymetallic oxide electrocatalyst for effective nitrate reduction to ammonia.The synergistic effects among the multiple elements in the electrocatalyst were clearly elucidated by comprehensive experiments.Specifically,Cu acted as the active site for reducing nitrate to nitrite,and Co facilitated the subsequent reduction of nitrite to ammonia,while Fe and Ni promoted water dissociation to provide protons.Furthermore,the incorporation of CeO_(2)increased the active surface area of(FeCoNiCu)Ox,resulting in an improved ammonia yield rate to meet industrial demands.Consequently,the(FeCoNiCu)Ox/CeO_(2)electrocatalyst achieved an ammonia current density of 382 mA cm^(-2)and a high ammonia yield rate of 30.3 mg h^(-1)cm^(-2)with a long-term stability.This work offers valuable insights for the future design of highly efficient multi-element electrocatalysts.
电催化硝酸根还原反应(NO_(3)^(-)RR)被认为是一种有前景且可持续的氨(NH_(3))合成新方法,但生成NH_(3)的选择性和产率受到析氢副反应和复杂八电子转移过程的限制.本文开发了一种(FeCoNiCu)Ox/CeO_(2)多金属氧化物电催化剂,能够将NO_(3)^(-)高效还原为NH_(3).文章通过设计系列实验,揭示了催化剂中不同元素之间的协同作用:Cu作为活性位点用于将NO_(3)^(-)还原为NO_(2)^(-),Co作为中继位点促进NO_(2)^(-)进一步还原为NH_(3),Fe和Ni则通过加速水解离保证了反应所需的质子供应.此外,CeO_(2)的加入显著增加了(FeCoNiCu)Ox多金属氧化物的活性表面积,进而提高了NH_(3)产率.最终,(FeCoNiCu)Ox/CeO_(2)电催化剂实现了高的NH_(3)电流密度(382 mA cm^(-2))和NH_(3)产率(30.3 mg h^(-1)cm^(-2)),兼具优异的长期稳定性.本项工作推动了多元素氧化物在电催化领域的应用,为高效多元素电催化剂的设计提供了有价值的见解.
作者
Yaning Qie
Jiachen Gao
Siqi Li
Mingjin Cui
Xuejiao Mao
Xinyu Wang
Bo Zhang
Sijia Chi
Yiran Jia
Quan-Hong Yang
Chunpeng Yang
Zhe Weng
郄亚宁;高嘉辰;李思琪;崔铭锦;毛雪娇;王新宇;张渤;池思伽;贾怡然;杨全红;杨春鹏;翁哲(Nanoyang Group,Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage,School of Chemical Engineering and Technology,and Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin University,Tianjin,300072,China;National Industry-Education Integration Platform of Energy Storage,Tianjin University,Tianjin,300072,China;Haihe Laboratory of Sustainable Chemical Transformations,Tianjin,300192,China;Institute of Energy Materials Science,University of Shanghai for Science and Technology,Shanghai,200093,China)
基金
supported by the National Natural Science Foundation of China(51972223,52202279)
the Natural Science Foundation of Tianjin(20JCYBJC01550)
the National Industry-Education Integration Platform of Energy Storage
the Fundamental Research Funds for the Central Universities
the Haihe Laboratory of Sustainable Chemical Transformations。
