Abstract:

Significance Silk fibroin （SF）-based flexible electronic devices are a new type of flexible electronic technology which utilize the excellent biocompatibility， degradability and mechanical flexibility of silk fibroin to achieve electronic functions through material modification and structural design. Silk fibroin matrix not only serves as a flexible substrate to carry circuits but also acts as an active medium to participate in sensing/response. Its transparency and controllable degradation characteristics are particularly suitable for implantable medical devices， environmentally friendly electronics and other fields. Typical applications include biosensors， wearable health monitoring devices and transient electronic devices. Their Young's modulus （1-10 GPa） is well matched with human tissues， enabling seamless wearing. By regulating the β -lamellar crystallinity of silk fibroin filbroin， the mechanical properties and degradation rate of the device can be precisely controlled. Currently， the main challenges are to improve the stability of electrical conductivity and the large-scale preparation process.

Progress In recent years， silk fibroin-based flexible electronic devices， mainly based on three forms of SF films， hydrogels and fibers， have made remarkable progress. In terms of material modification， researchers have continuously optimized the flexibility， electrical properties， environmental stability， and interfacial adhesion of SF materials by conducting in-depth studies on the structural composition of SF， adding plasticizers （such as glycerol and water）， incorporating metal ions （such as Ca²⁺）， introducing nanomaterials， mixing in polymer compounds， and chemically modifying the SF molecular chains. In the field of devices， various types of SF-based sensors， energy accumulators and memristors have emerged. Sensors are widely used in medical health and environmental monitoring. Energy accumulators can achieve wireless power supply. The application of neural memristors in artificial synapses for neuromorphic computing， high-density storage and the creation of artificial synapses is constantly expanding. Based on the continuous improvement of material modification and device performance， innovative SF-based electronic devices with self-healing， high flexibility， strong interface adhesion and degradability have emerged. In addition， pages have emerged one after another， and multi-functional device integrated systems integrating perception， information storage and self-power supply have also been realized.

Conclusion and prospect Research on SF flexible electronic devices has achieved fruitful results. Significant progress has been made in terms of flexibility， functionality， environmental stability， degradability， and air permeability， and the application scope has been continuously expanded. However， the following directions still needs to be carried out around SF material-based flexible electronic devices： The first is the optimization of material properties. Further research is conducted on the molecular structure and crystallization characteristics of silk fibroin. By regulating the crystallinity and arrangement of molecular chains of silk fibroin， combined with the doping of nanomaterials， chemical modification and structural regulation are carried out to further improve the electrical properties of silk fibroin as well as its mechanical properties such as flexibility， tensile strength and toughness. Precisely regulate its biodegradation rate to enable it to degrade within the organism at the expected time and in the expected manner， thereby reducing potential risks to the organism. The second is the innovation in the preparation process， developing more environmentally friendly and sustainable extraction and processing techniques for silk fibroin to reduce e

Key words: silk fibroin, flexible electronic device, preparation process, performance optimization, wearable sensor, biomemristor