近年来, AgNWs(Ag Nanowires)透明电极由于良好的导电性、优秀的韧性, 作为氧化铟锡(ITO)的替代材料受到了广泛的关注, 可以用于多种电子设备, 如触摸屏、有机太阳能电池和显示器等。但是, 在近年的透明电极应用中, 低长径比所带来的雾度过高、导电性较差的缺陷使AgNWs不能广泛地推广, 所以提高长径比是迫在眉睫的。本文采用一步多元醇法制备AgNWs, 探究不同分子量的混合PVP体系参与反应对包覆效果及生长过程的影响。研究结果表明, 与单一分子量PVP体系相比, PVP混合体系在生长过程中的再次形核点减少, AgNWs的长径比更高; 分子量为1 300 000与分子量为58 000的PVP按2∶1的比例混合, AgNWs 宽度最小, 长径比最高可达到1 200以上。

In recent years, Ag nanowire-based transparent electrodes have received extensive attention as an alternative to indium tin oxide (ITO) owing to their excellent electrical conductivity and excellent toughness. They are used in a variety of electronic devices, such as touch screens, organic solar energy batteries, monitors, etc. However, in the application of transparent electrodes, low haze, and hence the poor conductivity arising from low aspect ratio Ag nanowires limit their usage, and hence, it is of urgency to increase the aspect ratio of these wires. In the investigation, Ag nanowires were prepared by a one-step polyol method, and the effects of mixed poly (vinylpyrrolidone) (PVP) with different molecular weights on the coating and growth process were investigated. During the growth process, the coating of the mixed molecular weight PVP on the surface of Ag nanowires allows them to grow in a single direction while reducing their width, thereby increasing the aspect ratio. The outcome of study demonstrates that the re-nucleation point of the PVP system is smaller than that of the single-molecular-weight PVP system, and the aspect ratio of Ag nanowires is higher. The molecular weights of 1 300 000 and 58 000 are fused by a weight ratio of 2∶1, and at this point, the formed Ag nanowires possessed the smallest width and the longest length to display a higher aspect ratio of up to 1 200 or more.