Electrodeposition of Cobalt-Phosphate Oxygen Evolution Catalyst on Inert Electrode for Electrolysis.

This study describes the electrodepositon of potentially competent oxygen evolution catalyst on inert anode using phosphate buffered solution containing cobalt ions. The thickness of deposited amorphous cobalt-phosphate catalyst thin film varies depending on the deposition potential and deposition time. The electrodeposited catalyst can actively be used to improve water oxidation reaction under neutral condition.

Effect of Deposition Height on Nanostructure of Tungsten Oxide Thin Films in Flame Vapor Deposition Process.

Vertically aligned nanostructured tungsten oxide thin films have been found useful in many applications due to its intrinsic photonic and electronic properties. In this study, we directly prepared vertically aligned nanostructures including nanowires and nanotubes grown directly on FTO-coated glass by a newly designed flame vapor deposition system. The deposition height was found to be an important parameter for the development of thin film morphology. The evolution of nanowires and nanotubes with time was investigated. Based on our observation, the feasible growth mechanisms of distinct nanostructures were proposed.

Morphology Control of Tungsten Oxide Thin Films in an Aerosol Flame Deposition System.

Tungsten oxide thin film has been found great potential use in various applications such as smart window, gas sensor and photoelectrochemical cell due to their unique electrochromic, gas-chromic and electrochemical properties. The thin film morphology has been considered as an efficient limiting aspect for its performance. In this work, we successfully prepared tungsten oxide thin films with distinctive nanostructures on conductive glass in a flame vapor deposition process. The morphology of tungsten oxide thin films could be controlled by adjusting various process variables, including methane-oxygen ratio, deposition height and support substrate temperature. 1-D nanowires and nanotubes could be obtained in fuel rich flame at high substrate support temperature and 3-D nanocolumns could be easily formed in fuel lean flame. This work offers a rapid, economic approach for the growth of tungsten oxide thin film with controlled morphology.

Flame Synthesized Single Crystal Nanocolumn-Structured WO3 Thin Films for Photoelectrochemical Water Splitting.

Tungsten oxide thin films have been found as an active visible light driven photoanode material for photoelectrochemical water splitting due to its good stability in aqueous solution and energetically favorable valence band position for water oxidation. Morphology control, which determines the performance of WO3 photoanode, is one of most focuses of recent research interests. In this work, we successfully prepared monoclinic WO3 thin films on ITO glass at low range of substrate temperature with a fabrication rate around 100 nm per minute by using aerosol flame deposition process. Single crystal nanocolumns with both triangular pyramid-like and triangular prism-like structure were obtained at certain process conditions. Photoelectrochemical properties of photoelectrodes assembled with both structured WO3 thin films were investigated. The prism-like nanocolumn-structured thin film generated the current density of 1.58 mAcm(-2) at potential of 1.0 V versus Ag/AgCl in 0.5 M H2SO4 solution under illumination of AM 1.5 simulated solar light (100 mVcm(-2)). It presented superior photoelectrochemical performance to pyramid-like nanocolumn-structured WO3 thin film.