Effect of surfactant on electrochemical performance of Co3O4 electrode and its application in supercapacitor

Porous nanoflower-like Co 3 O 4 material on conductive nickel foam substrate was synthesized by hydrothermal reaction combined with thermal decomposition method. The effects of surfactants on the morphology and electrochemical properties of Co 3 O 4 electrodes were investigated. The Co 3 O 4 electrodes modified with SDS, PVP and CTAB surfactants exhibited nano-flower, nano-rod and honeycomb array structures, respectively. Compared with PVP and CTAB, the addition of SDS surfactant can promote the connection of nanostructures in the solution-recrystallization process, provide a large activity area, and reduce the crystallinity of materials. In addition, SDS inserted into the interlayers is decomposed to form the hierarchical flower-like structure. The Co 3 O 4 -SDS sample displayed superior electrochemical properties. At the current density of 1 A g − 1 , the specific capacitance of Co 3 O 4 -SDS was 1150 F g − 1 . The specific capacitance retention was 74% after 5000 charge-discharge cycles at the current density of 8 A g − 1 . The maximum energy density of the assembled Co 3 O 4 -SDS//AC supercapacitor reached 30 Wh kg − 1 even though the power density was 813 W kg − 1 . The energy density remained 9.0 Wh kg − 1 as the power density increased to 16,200 W kg − 1 .