Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Sciences, Niezapominajek 8, 30-232 Kraków, Poland.
Nanotechnology. 2019 Jan 4;30(1):015601. doi: 10.1088/1361-6528/aae677. Epub 2018 Oct 25.
Nickel-silver core-shell (Ni@Ag) nanoparticles (NPs) were formed in a two-step process: (1) the formation of a dispersion of Ni NPs; and (2) the transmetalation (galvanic displacement) reaction, where the surface of the Ni NPs acted as the reducing agent of Ag ions. Ni NPs were synthesized by the 'wet' chemical method, i.e., by the reduction of metal ions by using NaBH as the reducing agent. The influence of the concentration of polymeric stabilizer, reducing agent and Ag precursor on the properties of synthesized NPs was evaluated. In the optimal condition of synthesis, Ni@Ag NPs with about 50 and 210 nm-diameter Ni core coated with a thin (∼10-20 nm) Ag shell, were obtained. Finally, the stability of the synthesized spherical-shaped Ni@Ag NPs was tested and the results indicate long-term stability against aggregation and Ni oxidation. Thus, the resulting NPs are promising candidates for application in electronic devices, e.g., as components of conductive inks or pastes.
镍银核壳（Ni@Ag）纳米粒子（NPs）通过两步法形成：（1）形成 Ni NPs 的分散体；（2）转金属（电置换）反应，其中 Ni NPs 的表面充当 Ag 离子的还原剂。Ni NPs 通过“湿”化学方法合成，即通过使用 NaBH 作为还原剂还原金属离子。评估了聚合物稳定剂、还原剂和 Ag 前体的浓度对合成 NPs 性能的影响。在最佳的合成条件下，得到了直径约为 50 和 210nm 的 Ni 核包覆着薄（约 10-20nm）Ag 壳的 Ni@Ag NPs。最后，测试了合成的球形 Ni@Ag NPs 的稳定性，结果表明其具有长期的抗聚集和 Ni 氧化稳定性。因此，所得到的 NPs 有望应用于电子设备，例如作为导电油墨或糊剂的组成部分。
