Construction of three-dimensional MnO2/Ni network as an efficient electrode material for high performance supercapacitors

With the rapid growing interest and the usage of smart electronics devices, a considerable attention has been paid to improve the performance of energy storage devices. Herein, the 3D-MnO2/Ni electrode was fabricated using hydrogen bubble dynamic template (HBDT)-assisted electrodeposition method, in which several Ni nanoparticles were interconnected, arranged perpendicular to the substrate and formed the dendritic nanowall structure (3D-Ni current collector). This unique microstructure provides numerous of open pores, conductive network, more number of electroactive surface sites for the enhanced charge storage properties. The as-prepared 3D-MnO2/Ni network exhibited a high specific capacitance of 370 F g(-1) (295 mF cm(-2)) at 5 mV s(-1) with a remarkable rate capability compared to the MnO2/Ni. In addition, the 3D-MnO2/Ni electrode displays excellent long-term stability preserving a capacitance retention of 97% and a coulombic efficiency of 100% even after 5000 cycles. The present results demonstrate that the binder and conductive additive-free 3D architecture porous electrode opens up a new avenue in the fabrication of high surface area porous electrodes for high-performance supercapacitors. (C) 2020 Elsevier Ltd. All rights reserved.