ZIF衍生的CoSe₂纳米粒子在CuO@NiMn-LDH异质结构上的原位选择性硒化用于高性能超级电容器

In-Situ Selective Selenization of CoSe₂ Nanoparticles Derived from ZIF on CuO@NiMn-LDH Heterostructure for High Performance Supercapacitors

摘要: 随着能源危机和环境污染问题的日益加剧，开发高效环保的储能技术成为研究热点。超级电容器因其优异的功率密度与循环稳定性，在诸多领域展现出广阔前景。然而，其能量密度偏低急需通过先进电极材料加以提升。泡沫铜衍生的铜基化合物具有良好导电性与稳定性，是构建自支撑电极的理想模板，但其单一结构仍存在性能瓶颈。将其与层状双氢氧化物(LDHs)复合构建核壳型结构，能够有效弥补各自缺陷，提升电化学性能。金属有机框架(MOFs)作为多孔前驱体，硫化处理后导电性与活性显著增强，然而硒化方法仍存在能耗高、成本大等问题。为此，本文提出一种在室温条件下，利用硒粉与NaBH₄对ZIF-67与CuO复合材料进行选择性硒化的策略，成功构筑了Cu_1.8Se@NiMn-LDH@CoSe₂三维分级结构电极材料。该材料在10 mA∙cm⁻²下表现出高达11.64 F∙cm⁻²的面积比容量，并在5000圈后保持88.13%的容量。组装器件在9 mW∙cm⁻²下实现2.20 mWh∙cm⁻²的能量密度，经过5000圈后容量保持率和库仑效率分别可达99.93%和99.86%。本研究为MOF衍生金属硒化物的绿色合成提供了新路径，并为高性能超级电容器电极的设计提供了重要参考。

Abstract: With the intensification of the global energy crisis and environmental pollution, the development of efficient and eco-friendly energy storage technologies has become a research hotspot. Supercapacitors, owing to their excellent power density and cycling stability, have shown broad application prospects in various fields. However, their relatively low energy density remains a major bottleneck, which calls for the development of advanced electrode materials. Copper-based compounds derived from copper foam possess good electrical conductivity and chemical stability, making them ideal templates for constructing self-supporting electrodes. Nonetheless, their single-phase structures still suffer from performance limitations. Integrating these materials with layered double hydroxides (LDHs) to form core-shell architectures can effectively compensate for individual shortcomings and enhance electrochemical performance. Metal-organic frameworks (MOFs), as porous precursors, exhibit significantly improved conductivity and redox activity after sulfuration treatment; however, selenization methods are still hindered by high energy consumption and cost. In this study, we propose a room-temperature strategy using elemental selenium and NaBH₄ to selectively selenize a ZIF-67/CuO composite, successfully constructing a Cu1.8Se@NiMn-LDH@CoSe₂ hierarchical electrode material. This material delivers a high areal capacitance of 11.64 F∙cm⁻² at a current density of 10 mA∙cm⁻², with a capacity retention of 88.13% after 5000 cycles. The assembled device achieves an energy density of 2.20 mWh∙cm⁻² at a power density of 9 mW∙cm⁻², with capacity retention and Coulombic efficiency reaching 99.93% and 99.86%, respectively, after 5000 cycles. This work not only provides a green and low-temperature synthetic route for MOF-derived metal selenides but also offers a promising strategy for designing high-performance supercapacitor electrodes.