Cobalt molybdate nanoflake-assembling porous pillar array for high performance pseudocapacitor

•CoMoO4 nanoflake-assembling porous pillar array.•Large surface area, high porosity, and small size of nanoflake.•Pseudocapacitance performances are markedly improved.

CoMoO4 nanoflake-assembling porous pillar array is synthesized on Ni foam by a facile hydrothermal method. XRD, SEM and TEM demonstrate that CoMoO4 nanoflakes like flower petals cross and stack to form the porous pillar. As electrode materials of supercapacitors, CoMoO4 nanoflake-assembling porous pillar array show two pair of redox CV peaks, and the charging-discharging curves are also non-linear. This suggests its pseudocapacitance nature. A maximum areal specific capacitance of 1.92 F cm−2 is obtained at 4 mA cm−2. The galvanostatic cycling test and rate test reveal good cycling stability and rate capability.