Nano-architectured porous Mn2O3 spheres/cubes vs rGO for asymmetric supercapacitors applications in novel solid-state electrolyte

In this study, we have proposed a facile cost-effective hydrothermal route to synthesis homogeneously dispersed porous cubic structure Mn2O3 nanospheres (230 nm) and nanocubes (250 nm) nano-architectures to fabricate an efficient energy storage device. Mesoporous Mn2O3 spheres and cubes are exhibiting higher specific surface area (36.27 cm(3) g(-1) and 17.87 cm(3)g(-1)) and pore size (4.88 nm and 3.64 nm) respectively and in three electrode cell configuration they are showing an excellent specific capacitance of 345 F g(-1) and 321 F g(-1) at 0.2 A g(-1), respectively. Notably, the fabricated asymmetric solid-state supercapacitor (Mn2O3 nanospheres/nanocubes (positive electrode) and rGO electrodes (negative electrode)) are presenting an outstanding electrochemical performances with novel PVA-LiNO3 gel solid-state electrolyte; ultrahigh energy density of 46 W h kg(-1) at a power density of 247 W kg(-1) and excellent capacitance retention of 95% after 5000 cycles are observed. Moreover, practical and operation ability of the device are successfully demonstrated by lighting up the 21 LEDs lights in series like ALU letters. Thus, the reported porous cubic Mn2O3 nano-architectured electrode material synthesis strategy is more beneficial to the low cost, mass production for superior energy storage and viable alternative material for the existing commercially available materials.