Wang Miao, Yang Hao, Shi Jinan, Chen Yufeng, Zhou Yuan, Wang Liguang, Di Sijia, Zhao Xuan, Zhong Jun, Cheng Tao, Zhou Wu, Li Yanguang
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, China.
School of Physical Sciences University of Chinese Academy of Sciences, Beijing, 100049, China.
Angew Chem Int Ed Engl. 2021 Mar 8;60(11):5771-5777. doi: 10.1002/anie.202013047. Epub 2021 Jan 26.
Bifunctional hydrogen electrocatalysis (hydrogen-oxidation and hydrogen-evolution reactions) in alkaline solution is desirable but challenging. Among all available electrocatalysts, Ni-based materials are the only non-precious-metal-based candidates for alkaline hydrogen oxidation, but they generally suffer from low activity. Here, we demonstrate that properly alloying Ni with Mo could significantly promote its electrocatalytic performance. Ni Mo alloy nanoparticles are prepared from the reduction of molybdate-intercalated Ni(OH) nanosheets. The final product exhibits an apparent hydrogen-oxidation activity exceeding that of the Pt benchmark and a record-high mass-specific kinetic current of 79 A g at an overpotential of 50 mV. A superior hydrogen-evolution performance is also measured in alkaline solution. These experimental data are rationalized by our theoretical simulations, which show that alloying Ni with Mo significantly weakens its hydrogen adsorption, improves the hydroxyl adsorption and decreases the reaction barrier for water formation.
在碱性溶液中进行双功能氢电催化（氢氧化和析氢反应）是理想的，但具有挑战性。在所有可用的电催化剂中，镍基材料是碱性氢氧化反应中唯一的非贵金属基候选材料，但它们通常活性较低。在此，我们证明将镍与钼适当合金化可显著提高其电催化性能。镍钼合金纳米颗粒是通过还原插入钼酸盐的氢氧化镍纳米片制备的。最终产物表现出超过铂基准的明显氢氧化活性，在50 mV过电位下具有创纪录的79 A g的质量比动力学电流。在碱性溶液中也测量到了优异的析氢性能。我们的理论模拟对这些实验数据进行了合理解释，结果表明镍与钼合金化显著减弱了其对氢的吸附，改善了羟基吸附，并降低了水形成的反应势垒。
