Lattice-mismatch is an important factor for the heteroepitaxial growth of core–shell nanostructures. A large lattice-mismatch usually leads to a non-coherent interface or a polycrystalline shell layer. In this study, a conformal Ag layer is coated on Cu nanowires with dense nanoscale twin boundaries through a galvanic replacement reaction. Despite a large lattice mismatch between Ag and Cu (∼12.6%), the Ag shell replicates the twinning structure in Cu nanowires and grows epitaxially on the nanotwinned Cu nanowire. A twin-mediated growth mechanism is proposed to explain the epitaxy of high lattice-mismatch bimetallic systems in which the misfit dislocations are accommodated by coherent twin boundaries.

中文翻译：

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高度晶格不匹配的Cu / Ag核-壳纳米线的双介导外延生长†

晶格失配是核-壳纳米结构异质外延生长的重要因素。较大的晶格失配通常会导致不连贯的界面或多晶壳层。在这项研究中，通过电流置换反应，在具有密集的纳米级孪晶边界的Cu纳米线上涂覆了一层保形的Ag层。尽管Ag和Cu之间存在较大的晶格失配（约12.6％），但Ag壳在Cu纳米线中复制了孪生结构，并在纳米缠绕的Cu纳米线上外延生长。提出了孪生介导的生长机理来解释高晶格失配双金属系统的外延，其中错配位错由相干孪晶边界容纳。