Synthesis of NiO nanoparticles for supercapacitor application as an efficient electrode material

Nickel oxide (NiO) powder has been fabricated by using a simple hydrothermal method. The effect of different electrolytes such as Na2SO4 and KOH on supercapacitor properties has been investigated. NiO powder was characterized by XRD, FT-IR, SEM, EDAX, surface wettability study and BET. XRD study revealed the monoclinic phase of NiO. The FT-IR was used to confirm presence of free Ni-O bond in NiO nanoparticles. The SEM analysis showed non-uniform aggregated nanoparticles. The EDAX was used for finding composition of the elements. The BET analysis was used for finding surface area and pore radius of NiO powder. The surface wettability study showed that contact angle was hydrophilic in nature. In KOH electrolyte NiO-carbon cloth (CC) electrode showed better performance, NiO electrode exhibited high specific capacitances (Cs) 132 Fg(-1) in KOH and 79 Fg(-1) in Na2SO4 electrolytes at the scan rate 5 mVs(-1) with good cycling stability (similar to 75 % retention after 500 cycles) in a KOH electrolyte.