Kuang Yun, Zhang Ying, Cai Zhao, Feng Guang, Jiang Yingying, Jin Chuanhong, Luo Jun, Sun Xiaoming
State Key Laboratory of Chemical Resource Engineering , Beijing University of Chemical Technology , Beijing 100029 , China . Email:
Center of Electron Microscopy , Department of Materials Science and Engineering , Zhejiang University , Hangzhou 310027 , Zhejiang , P. R. China.
Chem Sci. 2015 Dec 1;6(12):7122-7129. doi: 10.1039/c5sc01947h. Epub 2015 Sep 9.
Developing facial synthetic routes for fabrication of multimetallic nanocatalysts with open porous morphology, tunable composition and tailored crystalline structure is a big challenge for fabrication of low-cost electrocatalysts. Here we report on the synthesis of single-crystalline dendritic bimetallic and multimetallic nanocubes a solvothermal co-reduction method. These cubes show highly porous, complex 3D inner connections but single-crystalline structure. Tuning the reduction kinetics of metal precursors and introducing galvanic reaction at the active sites during growth were believed to be the keys for the formation of such unique nanostructure. Electro-catalytic oxygen reduction (ORR) and methanol oxidation (MOR) on these catalysts showed dramatic enhancements for both cathodic and anodic electrocatalysis in fuel cells, which were attributed to their unique morphology and crystalline structure, as well as synergetic effect of the multi-metallic components. This work uncovers the formation mechanism of such complex single-crystalline dendritic multimetallic nanocrystals and offers a promising synthetic strategy for geometric and crystalline control of multimetallic nanocrystals with tailored physical and chemical properties, which will benefit the development of clean energy.
开发用于制备具有开放多孔形态、可调组成和定制晶体结构的多金属纳米催化剂的面部合成路线，对于低成本电催化剂的制备来说是一项巨大挑战。在此，我们报道了通过溶剂热共还原法合成单晶树枝状双金属和多金属纳米立方体。这些立方体呈现出高度多孔、复杂的三维内部连接，但却是单晶结构。人们认为，调节金属前驱体的还原动力学以及在生长过程中在活性位点引入电化反应是形成这种独特纳米结构的关键。这些催化剂上的电催化氧还原（ORR）和甲醇氧化（MOR）在燃料电池的阴极和阳极电催化中均表现出显著增强，这归因于它们独特的形态和晶体结构，以及多金属组分的协同效应。这项工作揭示了这种复杂的单晶树枝状多金属纳米晶体形成机制，并为具有定制物理和化学性质的多金属纳米晶体的几何和晶体控制提供了一种有前景的合成策略，这将有利于清洁能源的发展。
