Mesoporous hybrid NiOx–MnOx nanoprisms for flexible solid-state asymmetric supercapacitors†
Abstract
Mesoporous hybrid NiOx–MnOx nanoprisms have been successfully prepared in this work. The synthesis process involves a facile solvothermal method for preparation of Ni–Mn precursor particles and a subsequent annealing treatment. These mesoporous hybrid NiOx–MnOx nanoprisms have a high surface area of 101.6 m2 g−1. When evaluated as electrode materials in supercapacitors, the as-prepared mesoporous hybrid NiOx–MnOx nanoprisms deliver a specific capacitance of 1218 F g−1 at a current density of 2.0 A g−1. More importantly, the mesoporous hybrid NiOx–MnOx nanoprisms were successfully used to construct flexible solid-state asymmetric supercapacitors. The device shows a specific capacitance of 149.1 mF cm−2 at 2.0 mA cm−2, a good cycling stability with only 2.9% loss of capacitance after 5000 charge–discharge cycles, and good mechanical flexibility under different bending angles. These results support the promising application of mesoporous hybrid NiOx–MnOx nanoprisms as advanced supercapacitor materials.