Red-ox reactions in aqueous solutions of Co(OAc)$_{2}$ and K$_{2}$S$_{2}$O$_{8}$ and synthesis of CoOOH nanolayers by the SILD method

CoOOH nanolayers were rst prepared by the successive ionic layer deposition (SILD) method using aqueous Co(OAc)$_{2}$ and K$_{2}$S$_{2}$O$_{8}$ solutions. The obtained nanolayers were investigated by SEM, EDX, XRD, FTIR spectroscopy and electrochemical techniques. SEM images showed that the layers formed by nanosheets of size approximately 80–100 nm which had a hexagonal crystal structure. Electrochemical study of nickel foam electrodes modi ed by CoOOH layer prepared by 50 SILD cycles demonstrates that speci c capacitance of the lm is 1520 F/g at current density 1 A/g. Repeated cycling for 1000 charge-discharge cycles demonstrates 2% capacitance fade, so such electrodes may be used as pseudocapacitor electrodes.