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Cobalt diselenide (CoSe2) has drawn great concern as an anode material for sodium-ion batteries due to its considerable theoretical capacity. Nevertheless, the poor cycling stability and rate performance still impede its practical implantation. Here, CoSe2/nitrogen-doped carbon-skeleton hybrid microcubes with a TiO2 layer (denoted as TNC-CoSe2) are favorably prepared via a facile template-engaged strategy, in which a TiO2-coated Prussian blue analogue of Co3[Co­(CN)6]2 is used as a new precursor accompanied with a selenization procedure. Such structures can concurrently boost ion and electron diffusion kinetics and inhibit the structural degradation during cycling through the close contact between the TiO2 layer and NC-CoSe2. Besides, this hybrid structure promotes the superior Na-ion intercalation pseudocapacitance due to the well-designed interfaces. The as-prepared TNC-CoSe2 microcubes exhibit a superior cycling capability (511 mA h g–1 at 0.2 A g–1 after 200 cycles) and long cycling life (456 mA h g–1 at 6.4 A g–1 for 6000 cycles with a retention of 92.7%). Coupled with a sodium vanadium fluorophosphate (Na3V2(PO4)2F3)@C cathode, this assembled full cell displays a specific capacity of 281 mA h g–1 at 0.2 A g–1 for 100 cycles. This work can be potentially used to improve other metal selenide-based anodes for rechargeable batteries.

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The largest mesh size ξ of a multicyclic branched polymer network results in special microrheological behavior and unique viscosity modification applications in solution.