I&EC 148 |
| A simple. low cost and high-throughput method for screening oxide materials for photoelectrolysis activity has been developed. The method involves ink jet printing of oxide precursors onto conductive glass substrates and, after pyrolysis, screening them in electrolytes for photoelectrolysis activity using a scanned laser. A ternary oxide, containing cobalt, aluminum and iron and not previously known to be active for the photoelectrolysis of water, was identified using this high throughput combinatorial technique. The composition and optimum thickness for photoelectrochemical response of the newly identified material was further refined using quantitative ink jet printing. Chemical analysis of bulk and thin film samples revealed that the material contains cobalt, aluminum and iron in a Co3O4 spinel structure with Fe and Al substituted into Co sites with a nominal stoichiometry of Co3-x-yAlxFeyO4 where x and y are about 0.18 and 0.30 respectively. The material is a p-type semiconductor with an indirect band gap of around 1.5 eV, a value that is nearly ideal for an efficient single photoelectrode for water photoelectroylsis. The need for optimized nanomorphologies for efficient water splitting devices will also be discussed, |
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Nanotechnology and the Environment: Emphasis on Green Nanotechnology
8:30 AM-12:30 PM, Thursday, April 10, 2008 Morial Convention Center -- Rm. 231, Oral
Division of Industrial & Engineering Chemistry |