Facile synthesis of flower-like CoMn₂O₄ microspheres for electrochemical supercapacitors

Facile synthesis of porous and hollow spinel materials is highly desirable for their extensive applications in energy storage fields. In this work, uniform and decentralized flower-like CoMn₂O₄ microspheres were synthesized and characterized for supercapacitor electrodes in neutral aqueous electrolyte. In this contribution, uniform microsphere precursors were firstly fabricated by a solvothermal method, followed by a low temperature calcination process for crystallization. A detailed study shows that the deionized (DI) water content plays an important role in the solvothermal process to optimize the morphology of the microspheres. In 1 M Na₂SO₄, the spinel electrode material has a working potential window as high as 1.1 V and a specific capacitance of 188 F g^-1. Besides, the electrode material exhibits excellent cycling stability by retaining 93% of its original capacitance after 1000 cycles. Therefore, the flower-like microspheres of CoMn₂O₄ spinel are promising candidates for supercapacitor applications.