title: Fabrication and Characterization of Thin Film Nickel Hydroxide Electrodes for Micropower Applications.
abstract: The utilization of micropower sources is attractive in portable microfluidic devices where only low-power densities and energy contents are required. In this work, we report on the microfabrication of patterned α-Ni(OH)2 films on glass substrates which can be used for rechargeable microbatteries as well as for microcapacitors. A multilayer deposition technique is developed based on e-beam evaporation, ultraviolet lithography, and electroplating/electrodeposition which creates thin-film electrodes that are patterned with arrays of micropillars. The morphology and the structure of the patterned electrode films are characterized by employing field emission scanning electron microscopy. The chemical (elemental) composition is investigated by using X-ray diffraction and X-ray photoelectron spectroscopy. Finally, cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge/discharge measurements are used to evaluate the electrochemical performance of the patterned thin film electrodes compared to patternless electrodes. We observe that patterning of the electrodes results in significantly improved stability and, thus, longer endurance while good electrochemical performance is maintained.
authors.affiliation: Queen's-RMC Fuel Cell Research Centre, Kingston, Ontario K7L 5L9, Canada.
authors.forename: Hamid
authors.initials: H
authors.lastname: Falahati
authors.affiliation: Queen's-RMC Fuel Cell Research Centre, Kingston, Ontario K7L 5L9, Canada.
authors.forename: Edward
authors.initials: E
authors.lastname: Kim
authors.affiliation: Queen's-RMC Fuel Cell Research Centre, Kingston, Ontario K7L 5L9, Canada.
authors.forename: Dominik P J
authors.initials: DP
authors.lastname: Barz
keywords: multilayer deposition; nickel hydroxide; surface patterning; thin-film electrode