透明导电银纳米线薄膜的制备及热稳定性研究

Preparation and Thermal Stability Study of Transparent Conductive Silver Nanowire Films

摘要:

银纳米线薄膜制备工艺简单，与柔性衬底兼容，光电性能优异，被视为最有可能替代传统ITO的柔性透明电极材料之一。银纳米线的细线径、高长径比是提升薄膜光电性能的关键。采用多元醇法制备了银纳米线，研究了AgNO₃添加方式、PVP分子量和成核控制剂对银纳米线形貌的影响。通过优化银纳米线的制备工艺，最终获得了线径为35.5 nm的银纳米线，其薄膜方阻低至147.5 Ω?sq^-1，在550 nm处透过率高达96.21%。为了提升银纳米线透明薄膜电极的热稳定性，开发了GZO/AgNWs/GZO“三明治”复合新结构。结果表明，该复合结构电极经过250 ℃热冲击，不仅仍然保持高透明（550 nm透过率为82.42%），而且方阻的增加值不超过78%。GZO/AgNWs/GZO“三明治”透明电极具有高热稳定性，为银纳米线透明电极的商业化应用提供有益借鉴。

Abstract:

Silver nanowire films are simple to prepare， compatible with flexible substrates and have excellent optoelectronic properties. They are regarded as one of the most likely flexible transparent electrode materials to replace conventional ITO. Small wire diameter and high aspect ratio are the keys to enhancing its optoelectronic performance. The silver nanowires were prepared by the polyol method， and the effects of AgNO₃ addition method， molecular weight of PVP， and nucleation control agent on the morphology of silver nanowires were investigated. By optimizing the preparation process of silver nanowires， silver nanowires with a wire diameter of 35.5 nm were finally obtained， the sheet resistance was as low as 147.5 Ω?sq^-1， and the transmittance at 550 nm was as high as 96.21%. To improve the thermal stability of silver nanowire transparent thin film electrodes， a new GZO/AgNWs/GZO "sandwich" composite structure was developed. The results showed that the composite structure not only maintained high transparency （transmittance at 550 nm was 82.42%） after thermal shock at 250 °C， but also the increase of sheet resistance did not exceed 78%. The GZO/AgNWs/GZO “sandwich” transparent electrode has high thermal stability， which provides a useful reference for the commercial application of silver nanowire transparent electrodes.