The textile is required to have a large surface area for obtaining high triboelectric output from the device. In order to increase the surface area, we realized a nanopatterned triboelectric layer on an Ag-coated textile despite the fact that the realization of a periodically well-aligned nanopatterns on the Ag-coated textile was so challenging. In fact, the making of nanopattern template on the Ag-coated textile had many technical limitations. For instance, growth temperature of the template should be adequately low in order to prevent any thermal damage to Ag as well as textile itself. We have utilized the solution growth method of ZnO nanorods on the Ag-coated textile at a low temperature of under 100℃ resulting in no thermal damage to Ag/textile. As grown well-aligned ZnO nanorod arrays on the Ag-textile act as a very good template for making PDMS nanopatterns. Beside, adhesion between substrate and nanostructure is another crucial aspect as a poor adhesion can lead to an inferior mechanical durability. However, by incorporating silicon based organic material as nanopatterened layer, we have achieved high mechanical robustness; indeed, we have demonstrated a sustainable operation over 12,000 cycles.
The wearable triboelectric nanogenerator have been utilized to harvest biomechanical energy for successfully powering LEDs, an LCD and a keyless vehicle entry system without any help of external power sources. Such self-powered operations demonstrate its potential applications for powering smart cloths, health care monitoring systems, personal electronics etc. by harvesting the biomechanical energy.
The triboelectric generation is a promising energy harvesting technology with the advantages of high output voltage and efficiency, low cost, high versatility and simplicity in structural design and fabrication, stability and robustness, as well as environmental friendliness. The textile however, offers additional benefits to the technology as as it can realize realize high performance triboelectric generators due to the strong triboelectricity of the micro scale fiber structures and is most suitable material for the wearable applications.
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