Ultra-tiny ZnMn₂O₄ nanoparticles encapsulated in sandwich-like carbon nanosheets for high-performance supercapacitors

Abstract

Known as an excellent energy storage material, ZnMnO has a wide range of applications in supercapacitors. In this report, a special sandwich-like structure of ZnMnO/C has been first designed and synthesized via a simple hydrothermal method and subsequent calcinations. The designed special sandwich-like structure can benefit ion exchange and remit the probable volume changes during a mass of electrochemical reactions. Furthermore, the porous carbon nanosheets, derived from low-cost glucose, can effectively increase ion flux. Therefore, the novel sandwich-like ZnMnO nanoparticles encapsulated in carbon nanosheets can undoubtedly demonstrate an exceptional electrochemical performance for SCs. In this work, the composite material with porous sandwich-like structure exhibits excellent cyclic stability for 5000 cycles (∼5% loss) and high specific capacitance of 1786 F g.

Synthesis of ZnMn2O4 Nanoparticles by a Microwave-Assisted Colloidal Method and their Evaluation as a Gas Sensor of Propane and Carbon Monoxide

“…ZnMn 2 O 4 is an interesting compound that has been widely used as an electrode for Li-ion batteries due to its low cost and being environmentally friendly [19,20,21,22,23,24]. Also, this material has been used as a supercapacitor [25,26,27,28,29] and thermistor [30] due to its structural, physical, and chemical properties. It has been reported that zinc manganite shows strong catalytic activity [31,32,33,34,35]; therefore, this material could perform well as a gas sensor.…”

“…In regard to the synthesis of nanometric ZnMn 2 O 4 , several routes have been commonly employed: polymer-pyrolysis [23], solid-state reaction [24], sol-gel [31], co-precipitation [33], hydrothermal [29,40], and solvothermal methods [41]. Reports on the synthesis of ZnMn 2 O 4 nanoparticles using a microwave-assisted route are still limited.…”

Recent progress in supercapacitors based on the advanced carbon electrodes

“…The utilization of binary metal oxides-particularly spinel, represented by AB 2 O 4 -as pseudocapacitive electrode including two transition metals A and B such as ZnMn2O4, has also been gaining increasing attention due to their multiple available oxidation states and richer redox processes [45]. In 2018, Mozaffar Abdollahifa et al [46] successfully synthesized carbon-coated ZnMn 2 O 4 utilizing a novel solution combustion approach which adopted polyethylene glycol as a multifunctional structure-directing agent.…”

Synthesis of a MnS/NixSy composite with nanoparticles coated on hexagonal sheet structures as an advanced electrode material for asymmetric supercapacitors

“… 30 Guan et al designed ZnMnO 4 nanoparticles encapsulated in carbon sheets and employed them for supercapacitors. 31 Therefore, a distinct micro-flower structure decorated with nanoparticles has been successfully synthesized in our research.…”