Improved Performance by SiO2 Hollow Nanospheres for Silver Nanowire-Based Flexible Transparent Conductive Films

Flexible transparent conductive films (TCFs) have attracted tremendous interest thanks to the rapid development of portable/flexible/wearable electronics. TCFs on the basis of silver nanowires (AgNWs) with excellent performance are becoming an efficient alternative to replace the brittle transparent metal oxide. In this study, a promising method was developed by introducing SiO2 hollow nano spheres (SiO2-HNSs) into the film to significantly improve the performance of AgNW-based TCFs. Since SiO2-HNSs have opposite charges to AgNWs, the strong attraction had promoted a uniform distribution of AgNWs and made the distance between AgNWs closer, which could decrease the contact resistance greatly. The introduction of SiO2 layer remarkably enhanced the transmission of visible light and the conductivity. In addition, the TCFs constructed by AgNWs and SiO2-HNSs showed, much higher thermal stability and adhesive force than those by only AgNWs. As an example, the transmission of AgNW/SiO2-HNS-coated poly(ethylene terephthalate) (PET) could increase about 14.3% in comparison to AgNW-coated PET. Typically, a AgNW/SiO2-HNS-based TCF with a sheet resistance of about 33 Omega/sq and transmittance of about 98.0% (excluding substrate) could be obtained with excellent flexibility, adhesion, and thermal stability. At last some devices were fabricated.