Department of Materials Science EngineeringBiodegradable and wearable self-powered devices have represented the emerging technology necessary to new life pattern of human. Silk fibroin-based biodegradable composite-type nanogenerators are demonstrated with controllable lifetime for powering to the implantable devices. The 2D thin film- and 1D wire-type composites consist of the well-dispersed lead-free ferroelectric (BaTiO3, ZnSnO3, Bi0.5(Na0.82K0.18)0.5TiO3, and K0.5Na0.5Nb0.995Mn0.005O3) nanoparticles. Ag nanowires are used to enhance the dispersion of the nanoparticles and polyvinylpyrrolidone prevents Ag nanowires from connecting with each other. A maximum output voltages and current densities of 2.2 V and 0.12 µA/cm2 in the thin film, and 1.8 V and 0.1 µA/cm2 in the wire are obtained under the motion of a foot step for when 30 wt% KNN:Mn nanoparticles are well-dispersed in the solution because of the largest piezoelectric coupling figure of merit. The properties of water-soluble composite films are also controlled with the glycerol up to 48 hrs. And textile structures are desirable for wearable device that are stretchable and flexible. In this article, new textile-structured triboelectric nanogenerators are demonstrated for powering to the wearable devices. The tube structured triboelectric nanogenerator consists of PDMS tube, copper wire in center of device, and aluminum wrapped around the outer surface of tube, which are utilized to generate and harvest triboelectricity. We also fabricate the cable structured triboelectric nanogenerator, which is composed of several tube structured nanogenerator with series connection, resulting in 3 times higher output voltage than that of a tube structured nanogenerator. Additionally, textile- structured triboelectric nanogenerator is fabricated with weaving from numerous tube structured triboelectric nanogenerator with parallel connection to generate high output current. A maximum output voltages and currents of 50 V and 180 µA for the textile-structured nanogenerator are obtained under the vertical stress of pushing tester. Moreover, the relationship between output performance and the amount of deformation at stretchable loading in the stretchable textile structured triboelectric nanogenerator is also investigated. This work should play an important role in new direction to wearable electronics.ope
