Journal of Colloid and Interface Science, Vol.563, 435-446, 2020
Construction of hierarchical cobalt-molybdenum selenide hollow nanospheres architectures for high performance battery-supercapacitor hybrid devices
Transition metal selenides have aroused widespread attention as a class of emerging electrode materials for high-performance supercapacitors attributed to their featured with high theoretical capacitance and low electronegativity. Nevertheless, their practical applications are seriously restricted by the large volume expansion during high-rate charge/discharge. It is imperative to reasonably construct tunable composition and attractive architectures for electrode materials at nanoscale to mitigate the issues. Herein, hierarchical cobalt-molybdenum selenide (denoted as CoSe2/MoSe2-3-1) hollow nanospheres architectures are purposefully prepared via an efficient gas bubble-templated method combined with post-annealing process. Benefiting from the rationally hierarchical hollow structures and maximized utilization ratio of active materials, the novel bimetallic selenides acquire superior electrochemical performance with high specific capacity (211.97 mA h g(-1) at 1 A g(-1)) and remarkable cycling stability (94.2% capacity retention over 2000 cycles at 3 A g(-1)). Significantly, the assembled CoSe2/MoSe2-3-1//activated carbon (AC) battery-supercapacitor hybrid (BSH) device renders a high energy density up to 51.84 W h kg(-1) at a power density of 799.2 W kg(-1) and preeminent cycling stability with 93.4% retention over 10,000 cycles. The present work provides an effective and rational design route to engineer advanced bimetallic selenides with hierarchical hollow structures for electrochemical energy storage and conversion. (C) 2019 Elsevier Inc. All rights reserved.