| The researches of biomedical, solar energy conversion, implantable or wearable devices are becoming the most popular hotspots. Substrates play a key role in the fabrication of optoelectronic devices. This paper proposes the use of silk fibroin(SF) to produce the composite conductive material with good flexibility, high transparency, which is contemplated to apply in implantable filed.In this paper, the common preparation, bonding mechanism, the role interface of the SF-based flexible transparent conductive film was introduced at first. The gold SF composite film, the graphene SF composite film and the silver nanowires SF (AgNWS-SF) composite film was try to prepare for characterization. Secondly, the morphology structural features, light transmittance, the conductivity, after bending conductivity, breaking strength, thermal properties of the composite film were detailed characterized by the advanced instruments (SEM, EDS, AFM, TG, etc.).By comprehensive comparison of various film prepared methods, AgNWS-SF composite film of the best performance and the prepare way were obtained, which was better than 80% transmittance (visible range), the sheet resistance was less than 16Ω, the thermal decomposition temperature of 270℃, fracture stress of 70～80 MPa, elongation at break was 3～4%. The films also retained conductivity even after being bent hundreds of times. This could be attributed to its embedded structure of the AgNWs. Furthermore, the biodegradable and mechanical properties of SF films could be used to control the fabrication process, matching requirements for some specific applications. These composite films show promise in future applications towards flexible electrodes, conducting materials and implantable devices.Finally, some applications were successfully produced by using the AgNWS:① Commercial LED chips were embedded on the SF-AgNWs films strips to form a conductive network circuit; the film was able to successfully light the LED chips. This indicates its ability to provide power to other optoelectronic devices. This luminescent strip can be bent or folded, catering to various wearable applications.② The conductive material and silk fabrics were prepared to become conductive composite fabric, which ensure the silk chiffon have high light transmittance with excellent conductivity, and also increasing the strength of the film. Therefore, the traditional silk textiles can be easily prepared as a touch screen, conductive fabric wearable electronic materials.③ The SF-AgNWS composite films were as counter electrode applied in DSSC. The J (V) characteristics of the solar cell under illumination, with composite film as the counter electrode, showed a short-circuit photocurrent density (Jsc) of 1.6 mA/cm2, an open circuit voltage (Voc) of 0.60 V, a fill factor (FF) of 0.22 and overall power conversion efficiency of 0.2%. These values indicate that the composite films have a large application prospect in photoelectric field as flexible transparent conductive electrodes.④ We have demonstrated that flexible and light OSCs with a PCE of 6.4% can be fabricated using SF films as a supporting substrate. These devices displayed excellent biodegradability. The results show that AgNWs integrated with a SF substrate displayed excellent conductivity, transmittance and flatness. After bending, the devices retain a stable conductivity that is superior to traditional flexible ITO-PEN substrates. The conductivity of bended AgNWs-SF substrates can be recovered by a "self-healing" process. We believe that with continuing efforts in research and development, high performance SF-based OSCs with extreme biocompatibility and human affinity will become reality. The realization of SF-based OSCs in commercial and everyday uses promises a bright future for optical-biological fields. |
PDF Full Text Request