Transition metal selenides (TMSs) are emerging battery-type materials for supercapacitors (SCs) because of their high theoretical capacities and excellent intrinsic conductivity. Nevertheless, the slow kinetics and inferior cycling stability restrict their practical applications. In this investigation, a novel heterostructure consisting of NiSe/MnSe nanospheres and CoS nanosheets anchored on a carbon paper (CP) skeleton is fabricated by a rational two-step electrodeposition approach. The interaction and cooperation between NiSe/MnSe and CoS not only boosts the electroactivity and electrical conductivity but also enhances the ion transportation rate and structural stability. The as-obtained NiSe/MnSe@CoS electrode achieves an increased specific capacity (884.0C/g/0.62C cm at 1 A/g), improved rate property (74.8 % at 20 A/g), and enhanced cyclic performance (85.4 % over 10,000cycles) when compared to pure NiSe/MnSe and CoS electrodes. Moreover, the constructed hybrid supercapacitor (HSC) delivers a maximal energy density of 65.8 Wh kg under a power density of 1212.3 W kg and outstanding long-cycle durability with 93.3 % capacity retention after 20,000cycles at 20 A/g. This research proposes a simple and sound strategy for realizing breakthroughs of TMSs-based electrode materials for HSC with high energy density and superior cyclic stability.

中文翻译：

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具有优异稳定性的超级电容器硒化镍/硒化锰@硫化钴异质结构的合成


过渡金属硒化物（TMS）因其高理论容量和优异的本征电导率而成为新兴的超级电容器（SC）电池型材料。然而，缓慢的动力学和较差的循环稳定性限制了它们的实际应用。在这项研究中，通过合理的两步电沉积方法制备了一种新型异质结构，该异质结构由锚定在碳纸（CP）骨架上的 NiSe/MnSe 纳米球和 CoS 纳米片组成。 NiSe/MnSe 和 CoS 之间的相互作用和配合不仅提高了电活性和电导率，而且还提高了离子传输速率和结构稳定性。所获得的 NiSe/MnSe@CoS 电极提高了比容量（1 A/g 时为 884.0C/g/0.62C cm），提高了倍率性能（20 A/g 时为 74.8%），并增强了循环性能（85.4 % 超过 10,000 次循环）与纯 NiSe/MnSe 和 CoS 电极相比。此外，所构建的混合超级电容器（HSC）在功率密度为1212.3 W kg时可提供65.8 Wh kg的最大能量密度，并具有出色的长循环耐久性，在20 A/g下循环20,000次后容量保持率为93.3%。这项研究提出了一种简单而合理的策略，以实现基于 TMS 的 HSC 电极材料的突破，具有高能量密度和优异的循环稳定性。