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Electrocatalytic energy conversion technologies, such as electrocatalytic decomposition of water to hydrogen, electrocatalytic reduction of carbon dioxide, and electrocatalytic reduction of nitrogen, are an important approach to replace fossil energy, reduce carbon emissions, and obtain renewable fuels. Electrocatalytic Oxygen Evolution ( OER) is an important and versatile anode half-reaction in the conversion of these electrocatalytic energy sources. However, OER is kinetically slow and requires an efficient oxygen evolution electrocatalyst to reduce the reaction energy barrier, thereby accelerating the OER process. After several decades As a result of efforts, a large number of highly efficient and stable alkaline OER electrocatalysts have been developed, but the development of the acidic OER electrocatalysts has had little success. Due to the higher mass transfer rate of electrocatalytic reactions in acidic PEM electrolysis cells, Product purity and efficiency, etc., so the development of high-efficiency acidic OER electrocatalyst has more important large-scale application significance. At present, the lack of high activity and stable acidic OER electrocatalyst still hinders the development of electrocatalytic energy conversion reactions in acidic media. A big bottleneck.
Recently, Chen Liang, a researcher at the New Energy Institute under the Ningbo Institute of Materials Technology and Engineering, the Chinese Academy of Sciences, has developed a highly active and stable OER that can be applied in acidic electrolytes based on the design of surface structures and electronic structures of electrocatalysts. Catalyst. In this study, Su Jianwei fabricated a Cu-doped RuO2 hollow octahedron material assembled from ultra-small nanocrystallites by ion-exchanged metal-organic framework derivatives as Ru precursors and calcined in air. This method reduces the grain size of RuO2 nanocrystals by lowering the calcination temperature so that high Miller index planes with low coordination numbers can be exposed. As an acidic oxygen evolution electrocatalyst, its overpotential at a current density of 10 mA/cm2 is only At 188mV, it showed better electrocatalytic oxygen evolution activity and stability than commercial RuO2 electrocatalyst. Tian Ziqi calculated by density functional theory simulations found that the three-coordinate Ru atoms on the high-energy surface are gradually oxidized during the reaction and thus become large. The amplitude reduces the reaction energy barrier of OER, while Cu doping can adjust the electronic structure of RuO2, thereby greatly improving its OER catalytic activity. Work Assembling Ultra-Small Copper-doped Ruthenium Oxide Nanocrystals into Hollow Porous Polyhedra: Highly Robust Electrocatalysts for Oxygen Evolution in Acidic Media was published in the "Advanced Materials": on (Advanced Materials, DOI 10.1002 / adma.201801351).
The above work received strong support from the National Fund Project, the Zhejiang Provincial Nature Fund Jieqing Project, the Ningbo Innovation Team and the China Postdoctoral Fund Project.
