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Asymmetric supercapacitors with high energy density based on helical hierarchical porous Na _x MnO₂ and MoO₂.

ABSTRACT: Helical hierarchical porous Na _x MnO₂/CC and MoO₂/CC, which are assembled from nanosheets and nanoparticles, respectively, are fabricated using a simple electrodeposition method. These unique helical porous structures enable electrodes to have a high capacitance and an outstanding cycling performance. Based on the helical Na _x MnO₂/CC as the positive electrodes and helical MoO₂/CC as the negative electrodes, high performance Na _x MnO₂/CC//MoO₂/CC asymmetric supercapacitors (ASCs) are successfully assembled, and they achieve a maximum volume C_sp of 2.04 F cm^-3 and a maximum energy density of 0.92 mW h cm^-3 for the whole device and an excellent cycling stability with 97.22% C_sp retention after 6000 cycles.

SUBMITTER: Lu XF

PROVIDER: S-EPMC5519956 | biostudies-literature |

REPOSITORIES: biostudies-literature

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