A Silk Fibroin and Ultra-Long Silver Nanowires Based Transparent Conductive Composite Film for Nanosensor Devices

In addition to flexible touch screens, organic flexible photoelectric films have broad application prospects. In this paper, a transparent and conductive composite film was prepared by embedding a conductive network of ultra-long silver nanowires with silk fibroin as the substrate material. The ultra-long length can help minimize the number of junctions between the nanowires on the conductive grid, which can reduce greatly the resistance and optical shielding effect of the conductive layer. To tune the flexibility of the film, an appropriate amount of calcium ions (Ca2+) could be added to the silk fibroin solution. The conductivity, light transmittance, and temperature, stress and humidity sensitivity of the composite films were characterized and proved satisfactory. Its capability of self-healing was also demonstrated. With the natural biocompatibility and self-healing ability, this silk fibroin film may be applied in biomedical science, such as an electronic skin that can detect multiple human health indicators.