Kitahara Masaki, Kubara Saori, Takai Azusa, Takimoto Daisuke, Enomoto Shinpei, Yamauchi Yusuke, Sugimoto Wataru, Kuroda Kazuyuki
Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Ohkubo-3, Shinjuku-ku, Tokyo 169-8555 (Japan), Fax: (+81) 3-5286-3199.
Materials and Chemical Engineering, Faculty of Textile Science and Technology, Shinshu University, Tokida-3, Ueda, Nagano 386-8567 (Japan).
Chemistry. 2015 Dec 21;21(52):19142-8. doi: 10.1002/chem.201503174. Epub 2015 Nov 20.
Mesoporous bimetallic Au-Pt with a phase-segregated heterostructure has been prepared by using mesoporous silica SBA-15 as a template. Au nanoparticles were prepared as a seed metal within the mesopores, and subsequently Pt was deposited, sandwiching the Au seeds. Energy-dispersive X-ray (EDX) spectral mapping showed that the framework of mesoporous bimetallic Au-Pt, prepared by removing the silica template with HF, was composed of Au nanoparticles joined with Pt nanowires. The Au/Pt ratio of the mesoporous bimetallic Au-Pt could be varied by controlling the number of Au deposition cycles. Pre-adsorbed CO (COad) stripping voltammetry of the mesoporous bimetallic Au-Pt showed that the surfaces of the joined bimetallic structure were electrochemically active. This could be attributed to the open framework structure having a high ratio of exposed bimetallic mesopore surfaces. The described preparative approach, involving a mesoporous silica template and stepwise deposition within the mesopores, enables control of the nanostructure of the bimetallic material, which is greatly promising for the further development of synthetic methodologies for bimetallic structures.
以介孔二氧化硅SBA - 15为模板制备了具有相分离异质结构的介孔双金属Au - Pt。在介孔内制备Au纳米颗粒作为种子金属，随后沉积Pt，将Au种子夹在中间。能量色散X射线（EDX）光谱映射显示，通过用HF去除二氧化硅模板制备的介孔双金属Au - Pt的骨架由与Pt纳米线相连的Au纳米颗粒组成。介孔双金属Au - Pt的Au/Pt比可通过控制Au沉积循环次数来改变。介孔双金属Au - Pt的预吸附CO（COad）溶出伏安法表明，连接的双金属结构表面具有电化学活性。这可归因于开放的骨架结构具有高比例的暴露双金属介孔表面。所描述的制备方法，包括介孔二氧化硅模板和在介孔内逐步沉积，能够控制双金属材料的纳米结构，这对于双金属结构合成方法的进一步发展非常有前景。
