Fe2O3 nanowire arrays on Ni-coated yarns as excellent electrodes for high performance wearable yarn-supercapacitor

Abstract

Fibrous supercapacitors with high energy/power densities are important energy supply systems for smart wearable devices. Kinds of yarn-cathodes were fabricated, however, high performance anode materials have not been developed to match with the reported cathodes. Additionally, the (volumetric/area) capacitance of yarn-supercapacitors are often limited by less active material deposition, as the yarn is not resistant to high temperature, and the metal conductive-layer is not corrosion resistant. So, a high mass-loading anode with high volumetric performance has not been fabricated. In this study, we report a novel kind of Fe2O3 nanowires arrays on Ni-coated textiles anodes to solve this problem. The nickel layer deposited on the low-cost polyester yarn was applied as high-conductivity current collector, and vertically aligned Fe2O3 nanowires grown on the nickel layer with high mass loading were used as high performance active materials (Fe2O3//Ni//Yarn). It is worth noting that the Fe2O3//Ni//Yarn-based anodes exhibit a high specific capacitance of 54.2 F cm−3 at a scan rate of 10 mv s−1, furthermore, a symmetrical all-solid-state yarn-supercapacitor based on the above electrodes show a capacitance of 969 mF cm−3 at 10 mv s−1. This work provide a good choice of yarn-anodes to match with the reported high performance cathodes for further yarn-supercapacitor designs.