Li Dongdong, Shen Heng, Cai Chao, Sun Tongbing, Zhao Yiping, Chen Li, Zhao Ning, Xu Jian
State Key Laboratory of Separation Membranes and Membrane Processes, School of Materials Science and Engineering, Tianjin Polytechnic University, West Binshui Road No. 399, Xiqing District, Tianjin 300387, P. R. China.
Beijing National Laboratory for Molecular Sciences, Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun North First Street 2, Haidian District, Beijing 100190, P. R. China.
ACS Omega. 2017 Apr 28;2(4):1738-1745. doi: 10.1021/acsomega.7b00039. eCollection 2017 Apr 30.
Catkin, a natural hollow fiber, is used as a template to fabricate light, flexible, and electrically conductive silver microtubes with a high aspect ratio. The template is functionalized with tannic acid (TA)-Fe coordination complexes. Because of the metal ion chelating ability and reducibility of TA, silver nanoparticles (Ag NPs) can be formed in situ on the fiber's surface. The as-formed Ag NPs can act as nucleation sites in subsequent electroless silver plating, leading to the formation of a compact and uniform silver coating on the microtube. The coating is constructed by densely packed Ag NPs of only 15 ± 5 nm in diameter. Because of the tight accumulation and small size of the Ag NPs, the resulting silver-coated microtubes, without any post-treatment, show an electrical resistivity of 1500 mΩ·cm at a bulk density of 0.6 g·cm. We find that the in situ formed nucleation sites and the stirring speed in the electroless plating play important roles in the formation of a silver coating with a high electrical conductivity. This method may be extended to fabricate conductive nanocoatings on other substrates.
柳絮，一种天然的中空纤维，被用作模板来制备具有高纵横比的轻质、柔性且导电的银微管。该模板用单宁酸（TA）-铁配位络合物进行功能化处理。由于TA的金属离子螯合能力和还原性，银纳米颗粒（Ag NPs）可以在纤维表面原位形成。所形成的Ag NPs可作为后续化学镀银中的成核位点，从而导致在微管上形成致密且均匀的银涂层。该涂层由直径仅为15±5 nm的紧密堆积的Ag NPs构成。由于Ag NPs的紧密堆积和小尺寸，所得的镀银微管无需任何后处理，在堆积密度为0.6 g·cm时显示出1500 mΩ·cm的电阻率。我们发现原位形成的成核位点和化学镀中的搅拌速度在形成高导电银涂层中起着重要作用。该方法可扩展到在其他基材上制备导电纳米涂层。
