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Ag/MnO₂ Composite Sheath-Core Structured Yarn Supercapacitors.

ABSTRACT: One-dimensional (1D) yarn or fiber-based supercapacitors that have small diameter, volume and high mechanical strength are needed due to the demands on power source for wearable electronics, micro-devices, and implantable medical devices. The composite sheath is fabricated on a commercially available CNT yarn substrate by alternating depositions of MnO₂ and Ag layers. Synergistic effect of high loading level of pseudocapacitive MnO₂ and reasonably improved rate-capability are achieved. In the composite sheath, the interconnected networks provide electrical contact between MnO₂ aggregates and adjacent Ag layer. The conductive Ag inter layers shorten the solid-state charge diffusion length in the MnO₂. Moreover, generated electrons during the charge/discharge process can be collected rapidly by the adjacent Ag layer, therefore, the great extents of MnO₂ could be loaded onto the surface of CNT core fiber electrode without a significant rate-capability degradation. Due to the high MnO₂ loading level, the composite sheath-core yarn supercapacitor showed excellent specific areal capacitance (322.2?mF/cm²) and according energy density (18.3?µWh/cm²).

SUBMITTER: Kim JH

PROVIDER: S-EPMC6127153 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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