Metal-Organic-Framework-Derived MCo₂O₄ (M=Mn and Zn) Nanosheet Arrays on Carbon Cloth as Integrated Anodes for Energy Storage Applications

Electrode materials with special microstructures derived from metal-organic frameworks (MOFs) exhibited high performance in electrochemical energy storage devices. In this manuscript, using freshly prepared Co−MOF nanosheet arrays as the self-sacrificed template, MCo₂O₄ (M=Mn and Zn) nanosheet arrays were successfully grown on carbon cloth (CC) by using a facile solution method. As-prepared MnCo₂O₄@CC and ZnCo₂O₄@CC were used as the integrated electrodes for supercapacitors and Li-ion batteries. Studies found that both integrated electrodes delivered high capacity and a long cycling life of 20 000 cycles with the capacity retention of 95.5 % for MnCo₂O₄@CC and 94.7 % for ZnCo₂O₄@CC at the current density of 50 mA cm⁻², respectively. Assembled into asymmetric supercapacitors with carbon nanosheet arrays@CC (CNS@CC), the obtained maximum energy densities were measured to be 25.6 Wh kg⁻¹ at the power density of 3.4 kW kg⁻¹ for MnCo₂O₄@CC//CNS@CC based device and 22.7 Wh kg⁻¹ at the power density of 4.1 kW kg⁻¹ for ZnCo₂O₄@CC//CNS@CC based device, respectively. In addition, both integrated electrodes also showed good lithium storage performance, delivering high capacities of 1289 mA h/g (MnCo₂O₄@CC) and 1376 mA h/g (ZnCo₂O₄@CC) even after 200 cycles at the current density of 1 A g⁻¹, respectively. The outstanding performances suggest the potential of both nanosheet arrays integrated electrodes for extensive applications in energy storage devices.