以液體/塑性金屬電極實現高撓性摩擦起電器之研製

Triboelectric generators (TEGs) can convert mechanical energy into electrical energy by friction, compression or bending actions, and then the electrical energy stored in a capacitor is provided to electronic components with low cost, high stability and efficiency. However, current electrode materials used in TEG devices are mainly metal and ITO films, which can’t endure high deflection and deformation. As a result, this project will use liquid metal and innovative plastic metal as electrode materials, and PDMS and PET are used as flexible substrates to achieve TEG devices with a size of 50 × 50 mm2, 180 degree bending available, output voltage ≧ 100 V, and average power ≧ 5 mW. The working items of this project are as followed: 1. Blend plastic metals and characteristics evaluation: GaIn and ceramic glaze powder are mixed to form a clay-like plastic metal. Different blending ratio will produce distinct plasticity, conductivity and scratchability, prior evaluation will be essential. 2. Friction layer micro/nanostructurized and surface modification: The project will use PDMS as the friction layer material, micro/nano-fabrication processes are used to produce array structures of pyramid, pillar, and line features. Besides, the surface modification is executed with the atmospheric plasma to improve the electron affinity of the substrate. The modified SiO2, Al2O3, AlN nanoparticles (200 to 500 nm) will be also added into PDMS/PET contact interface, to further enhance the friction characteristics of TEG devices. 3. TEG fabrication and package: Liquid metal or plastic metal films are coated with stencil printing techniques on the backside of the PDMS friction layer and the PET sliding layer as electrode. Their surface should be covered by PDMS film to prevent from metal oxidation. Then, elastic spacers (2 to 5 mm) are fixed between PDMS/PET contact interface to form a distance between PDMS/PET contact layers. Finally, the periphery is packaged with the adhesive tape to complete the TEG device with a size of 50 × 50 mm2. 4. TEG test and charging circuit design: The pressing and bending of TEG devices by a crank-slider mechanism is used to test the friction electrification effect. The change of frequency, force and angle during pressing or bending will affect the output voltage and current characteristics. To enhance the charging effect, TEG devices will be combined with bridge rectifier and store energy through the capacitor. It is expected TEG performance can achieve output voltage ≧ 100 V and average power ≧5 mW. 5. TEG practical application evaluation: The finished high-flexibility TEG devices will also be evaluated for some practical applications. For instance, TEG is placed in the sole, stitched in the clothes, or attached to shock absorbers to transfer life common mechanical energy into electrical energy and store in a capacitor. In addition, TEGs will also be applied as pressure sensor for monitoring the physiological signal of the hands/feet muscle and heartbeat to assess its practical feasibility in the field of biomedical application.