Synergistic induction of mesoporosity in metal oxide film electrode through electrohydrodynamic splitting of precursor and simultaneous soft templating

Abstract

Porous metal oxide films are formed over Ni foam using template-assisted electrospray deposition of precursor sol. Pluronic F127, a triblock organic copolymer surfactant as the template source is added to the respective metal acetate sols to prepare Ni and Co oxide films. The unique cubic phases of metal oxides with the meso-macroporous structure provide easier access for electrolyte ions for faradic charge storage. Hollow spherical and honeycomb-like morphologies, respectively in NiO, and Co3O4 film electrodes contributes to the specific capacities (108 mC cm−2 (270 mF cm−2) and 98 mC cm−2 (245 mF cm−2) respectively at 1 mA cm−2). These NiO and Co3O4 film electrodes, when placed with porous carbon films as counter electrode, derived from the electrospray coating of the polymer precursor shows specific energy at the levels of 11.7 Wh kg−1 and 18 Wh kg−1 respectively. The template-assisted electrospray approach reported here can be extended to the fabrication of other oxides, mixed metal oxides, or binary/ternary oxide systems.