In this work, we report a supercapacitor electrode material based on nano-flower like cobalt molybdate decorated on porous activated carbon derived from waste onion peels (β-CoMoO-POAC). The obtained POAC exhibits highly porous structure and after the hydrothermal treatment with salts of cobalt and molybdenum, we observed a uniform distribution of β-cobalt molybdate (β-CoMoO) as nano-flowers on the surface of POAC. The chemical composition, morphology and porosity of the materials were thoroughly analyzed using field emission scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, infrared spectroscopy and Brunauer–Emmet–Teller surface area measurement. Due to its flower like and highly porous morphology, β-CoMoO@POAC exhibits a high specific capacitance of 1110.72 F/g at a current density of 1 mA/cm with superior cyclic retention of 96.03% after 2000 cycles. The best electrochemical performance exhibited by β-CoMoO@POAC is mainly due to its high surface area and porous nature of the material which assists in active transport of ions. This study reveals the exceptional electrochemical properties of β-CoMoO@POAC which could be considered as a potential material for advanced energy storage devices.

中文翻译：

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钼酸钴纳米花装饰生物废物衍生的多孔活性炭纳米复合材料：超级电容器的高性能电极材料

在这项工作中，我们报道了一种基于纳米花状钼酸钴装饰的超级电容器电极材料，该材料装饰在源自废洋葱皮的多孔活性炭（β-CoMoO-POAC）上。所获得的POAC表现出高度的多孔结构，并且在用钴盐和钼盐进行水热处理后，我们观察到β-钼酸钴（β-CoMoO）以纳米花的形式均匀分布在POAC的表面上。使用场发射扫描电子显微镜、X 射线光电子能谱、X 射线衍射、红外光谱和 Brunauer-Emmet-Teller 表面积测量对材料的化学成分、形态和孔隙率进行了彻底分析。由于其花状和高度多孔的形态，β-CoMoO@POAC 在 1 mA/cm 的电流密度下表现出 1110.72 F/g 的高比电容，2000 次循环后循环保留率高达 96.03%。 β-CoMoO@POAC 表现出的最佳电化学性能主要归因于其高表面积和材料的多孔性质，有助于离子的主动传输。这项研究揭示了 β-CoMoO@POAC 优异的电化学性能，可被视为先进储能设备的潜在材料。