Wang Liping, Zhu Yajie, Wen Yunzhou, Li Shangyu, Cui Chunyu, Ni Fenglou, Liu Yunxia, Lin Haiping, Li Youyong, Peng Huisheng, Zhang Bo
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai, 200438, China.
Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, 215123, China.
Angew Chem Int Ed Engl. 2021 May 3;60(19):10577-10582. doi: 10.1002/anie.202100610. Epub 2021 Mar 30.
In electrochemical energy storage and conversion systems, the anodic oxygen evolution reaction (OER) accounts for a large proportion of the energy consumption. The electrocatalytic urea oxidation reaction (UOR) is one of the promising alternatives to OER, owing to its low thermodynamic potential. However, owing to the sluggish UOR kinetics, its potential in practical use has not been unlocked. Herein, we developed a tungsten-doped nickel catalyst (Ni-WO ) with superior activity towards UOR. The Ni-WO catalyst exhibited record fast reaction kinetics (440 mA cm at 1.6 V versus reversible hydrogen electrode) and a high turnover frequency of 0.11 s , which is 4.8 times higher than that without W dopants. In further experiments, we found that the W dopant regulated the local charge distribution of Ni atoms, leading to the formation of Ni sites with superior activity and thus accelerating the interfacial catalytic reaction. Moreover, when we integrated Ni-WO into a CO flow electrolyzer, the cell voltage is reduced to 2.16 V accompanying with ≈98 % Faradaic efficiency towards carbon monoxide.
在电化学储能和转换系统中，阳极析氧反应（OER）占能量消耗的很大比例。电催化尿素氧化反应（UOR）由于其较低的热力学电位，是OER有前景的替代反应之一。然而，由于UOR动力学缓慢，其在实际应用中的潜力尚未得到释放。在此，我们开发了一种对UOR具有优异活性的钨掺杂镍催化剂（Ni-WO ）。Ni-WO催化剂表现出创纪录的快速反应动力学（相对于可逆氢电极在1.6 V时为440 mA cm ）和0.11 s 的高周转频率，这比未掺杂W的催化剂高出4.8倍。在进一步的实验中，我们发现W掺杂剂调节了Ni原子的局部电荷分布，导致形成具有优异活性的Ni位点，从而加速了界面催化反应。此外，当我们将Ni-WO集成到CO流动电解槽中时，电池电压降至2.16 V，同时对一氧化碳的法拉第效率约为98%。
