Sodium dodecyl sulfate-assisted synthesis of flower-like NiCo2O4 microspheres with large specific surface area for supercapacitors

The porous urchin-like and flower-like NiCo2O4 microspheres have been synthesized by a mild hydrothermal method combined with a simple annealing treatment. With the addition of sodium dodecyl sulfate (SDS), the morphology of NiCo2O4 microspheres changes from the urchin-like to the flower-like. The flower-like NiCo2O4 microspheres(NCO-5) with a larger specific surface area of 158 m(2)/g constructed by interconnected nanosheets exhibit a higher specific capacitance of 1538 F/g at 10 A/g and an excellent cycling stability. When the current density is 10 A/g, high capacity retention ratio up to 92.3% can be achieved for the flower-like NiCo2O4 microspheres electrode after 2500 cycles. The enhanced electrochemical performance can be mainly attributed to the hierarchical porous framework with a large specific surface area. Therefore, the remarkable capacitive performance of the flower-like NiCo2O4 microspheres will undoubtedly make them more attractive for high performance supercapacitors. (c) 2018 Elsevier B.V. All rights reserved.