Han Yechuang, Wu Shouliang, Dai Enmei, Ye Yixing, Liu Jun, Tian Zhenfei, Cai Yunyu, Zhu Xiaoguang, Liang Changhao
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Shushanhu Road 350, Hefei, 230031, China.
Department of Materials Science and Engineering, University of Science and Technology of China, Jinzhai Road 96, Hefei, 230026, China.
Chemphyschem. 2017 May 5;18(9):1133-1139. doi: 10.1002/cphc.201601185. Epub 2017 Feb 17.
Laser melting in liquids (LML) is one of the most effective methods to prepare bimetallic alloys; however, despite being an ongoing focus of research, the process involved in the formation of such species remains ambiguous. In this paper, we prepared two types of Pt-based bimetallic alloys by LML, including Pt-Au alloys and Pt-iron group metal (iM=Fe/Co/Ni) alloys, and investigated the corresponding mechanisms of alloying process. Detailed component and structural characterizations indicate that laser irradiation induced a quite rapid formation process (not exceeding 10 s) of Pt-Au alloy nanospheres, and the crystalline structures of Pt-Au alloys is determined by the monometallic constituents with higher content. For Pt-iM alloys, we provide direct evidence to support the conclusion that FeO /CoO /NiO colloids can be reduced to elementary Fe/Co/Ni particles by ethanol molecules during laser irradiation, which then react with Pt colloids to form Pt-iM sub-microspheres. These results demonstrate that LML provides an optional route to prepare Pt-based bimetallic alloy particles with tunable size, components, and crystalline phase, which should have promising applications in biological and catalysis studies.
液体中的激光熔化（LML）是制备双金属合金最有效的方法之一；然而，尽管它一直是研究的重点，但此类合金形成过程所涉及的机制仍不明确。在本文中，我们通过LML制备了两种类型的铂基双金属合金，包括铂 - 金合金和铂 - 铁族金属（iM = Fe/Co/Ni）合金，并研究了合金化过程的相应机制。详细的成分和结构表征表明，激光辐照诱导了铂 - 金合金纳米球的快速形成过程（不超过10秒），并且铂 - 金合金的晶体结构由含量较高的单金属成分决定。对于铂 - iM合金，我们提供了直接证据来支持以下结论：在激光辐照期间，FeO /CoO /NiO胶体可以被乙醇分子还原为单质Fe/Co/Ni颗粒，然后这些颗粒与铂胶体反应形成铂 - iM亚微球。这些结果表明，LML提供了一种制备尺寸、成分和晶相可调的铂基双金属合金颗粒的可选途径，这在生物和催化研究中应具有广阔的应用前景。
