Synthesis of Cu doped Ba(OH)₂ thin film by SILAR method for supercapacitor electrode application

Abstract An economically suitable successive ionic layer adsorption and reaction (SILAR) method has been used to deposit 0.25, 0.50 and 0.75 wt% copper doped barium hydroxide on stainless steel (SS) substrate. X-ray diffraction analysis shows the orthorhombic crystal structure of Cu doped Ba(OH) 2 electrode. FTIR analysis reveals the chemical bonds present in the sample. The energy-dispersive x-ray spectroscopy (EDAX) and x-ray photo electron spectroscopy (XPS) measurements have been performed to confirm Cu doping into Ba(OH) 2 . The electrochemical properties of Cu doped Ba(OH) 2 electrode have been analysed by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques. The 0.50 wt% Cu doped barium hydroxide electrode exhibits the highest specific capacitance (C sp ) of 356.12 F g −1 (59.55 mF cm −2 ) at 1 mV s −1 scan rate in 1 M Na 2 SO 4 electrolyte solution. This electrode also shows <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>~</mml:mo> </mml:math> 85% capacitance retention up to 8000 cycles. A symmetric device has also been fabricated by using two electrodes. This device shows energy and power densities of 1.13 Wh Kg -1 and 279.7 W Kg -1 respectively. This cyclic retention and capacitive behaviour of Cu-doped Ba(OH) 2 shows its utility as an energy storage material in the near future.