Abstract The electrode materials with core-shell heterostructure draw researchers' attention in the fabrication of supercapacitors (SCs), which can reduce cost and prolong service lifespans. Herein, nickel‑cobalt selenide nanoparticles, which are anchored on carbon microsphere to form core-shell heterostructure composite, exhibit excellent specific capacitance (960 F g−1) and superior cycling lifetime (85% after 2000 cycles). Furthermore, a new asymmetric supercapacitor (ASC) is created by utilizing C-20@(Ni, Co)0.85Se and AC as cathode and anode. The C-20@(Ni, Co)0.85Se // AC ASC exhibits the largest energy density of 34.44 W h kg−1 at a power density of 1125.23 W kg−1 and superior cycling lifetime with 81.5% of capacitance retention after 5000 cycles. Thus, C-20@(Ni, Co)0.85Se // AC ASC is known as potential electrode materials for ASC devices.

中文翻译：

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导电碳球负载的硒化镍钴纳米粒子作为超级电容器的高性能和长寿命电极

摘要 具有核壳异质结构的电极材料在超级电容器（SCs）的制造中引起了研究人员的关注，它可以降低成本并延长使用寿命。在此，硒化镍钴纳米粒子固定在碳微球上形成核壳异质结构复合材料，表现出优异的比电容（960 F g-1）和优异的循环寿命（2000 次循环后为 85%）。此外，利用 C-20@(Ni, Co)0.85Se 和 AC 作为阴极和阳极创建了一种新的非对称超级电容器 (ASC)。C-20@(Ni, Co)0.85Se // AC ASC 在 1125.23 W kg-1 的功率密度下表现出 34.44 W h kg-1 的最大能量密度和优异的循环寿命，5000 年后电容保持率为 81.5%循环。因此，C-20@(Ni，Co)0。