Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore.
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
Adv Mater. 2017 Sep;29(36). doi: 10.1002/adma.201701331. Epub 2017 Jul 21.
Noble-metal nanomaterials are attracting increasing research interest due to their promising applications in electrochemical catalysis, for example. Although great efforts have been devoted to the size-, shape-, and architecture-controlled synthesis of noble-metal nanomaterials, their crystal-phase-controlled synthesis is still in its infancy. Here, for the first time, this study reports high-yield synthesis of Au nanorods (NRs) with alternating 4H/face-centered cubic (fcc) crystal-phase heterostructures via a one-pot wet-chemical method. The coexistence of 4H and fcc phases is relatively stable, and the 4H/fcc Au NRs can serve as templates for crystal-phase-controlled epitaxial growth of other metals. As an example, bimetallic 4H/fcc Au@Pd core-shell NRs are synthesized via the epitaxial growth of Pd on 4H/fcc Au NRs. Significantly, the 4H/fcc Au@Pd NRs show superior mass activity toward the ethanol oxidation reaction, i.e., 6.2 and 4.9 times those of commercial Pd black and Pt/C catalysts, respectively. It is believed that this new synthetic strategy can be used to prepare other novel catalysts for various promising applications.
贵金属纳米材料由于在电化学催化等方面具有广阔的应用前景，因此引起了越来越多的研究兴趣。尽管人们已经投入了大量的精力来控制贵金属纳米材料的尺寸、形状和结构，但它们的晶相控制合成仍处于起步阶段。在这里，首次通过一步湿法化学法报告了高产率合成具有交替 4H/面心立方（fcc）晶相异质结构的 Au 纳米棒（NRs）。4H 和 fcc 相的共存相对稳定，4H/fcc Au NRs 可以作为其他金属晶相控制外延生长的模板。例如，通过在 4H/fcc Au NRs 上外延生长 Pd，合成了双金属 4H/fcc Au@Pd 核壳 NRs。重要的是，4H/fcc Au@Pd NRs 对乙醇氧化反应表现出优异的质量活性，分别是商业 Pd 黑和 Pt/C 催化剂的 6.2 倍和 4.9 倍。相信这种新的合成策略可用于制备其他新型催化剂，以用于各种有前途的应用。
