title: Effects of Electrodeposition Mode and Deposition Cycle on the Electrochemical Performance of MnO2-NiO Composite Electrodes for High-Energy-Density Supercapacitors.
abstract: Nanostructured network-like MnO2-NiO composite electrodes were electrodeposited onto stainless steel substrates via different electrodeposition modes, such as chronopotentiometry, chronoamperometry, and cyclic voltammetry, and then subjected to heat treatment at 300°C for metal oxide conversion. X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy were used to study the crystalline natures and morphologies of the deposited films. The electrochemical properties were investigated using cyclic voltammetry and charge/discharge tests. The results revealed that the electrochemical performance of the as-obtained composite electrodes depended on the electrodeposition mode. The electrochemical properties of MnO2-NiO composite electrodes prepared using cyclic voltammetry exhibited the highest capacitance values and were most influenced by the deposition cycle number. The optimum specific capacitance was 3509 Fg-1 with energy and power densities of 1322 Wh kg-1 and 110.5 kW kg-1, respectively, at a current density of 20 Ag-1 in a mixed KOH/K3Fe(CN)6 electrolyte.
authors.affiliation: Centre for Ionics University of Malaya, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.lastname: Rusi
authors.affiliation: Centre for Ionics University of Malaya, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: S R
authors.initials: SR
authors.lastname: Majid
mesh_terms: D025802:Electric Capacitance; D055664:Electrochemical Techniques; D004566:Electrodes; D004595:Electroplating / Q000379:methods; D017895:Manganese Compounds / Q000737:chemistry*; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009532:Nickel / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017895:Manganese Compounds; D010087:Oxides; C027424:manganese oxide; D009532:Nickel; C028007:nickel monoxide