6533b82dfe1ef96bd1290a77
RESEARCH PRODUCT
Photoelectrochemical evidence of inhomogeneous composition at nm length scale of anodic films on valve metals alloys
Monica SantamariaHiroki HabazakiFrancesco Di FrancoFrancesco Di QuartoAndrea Zafforasubject
Materials scienceBand gap020209 energyGeneral Chemical EngineeringPhotoelectrochemistryAnalytical chemistryOxideQuantum yield02 engineering and technologyPhoton energyAnodizingElectrochemistryN incorporationchemistry.chemical_compoundPhotoelectrochemistry0202 electrical engineering electronic engineering information engineeringElectrochemistryChemical Engineering (all)Double-layered anodic filmAnodizingMetallurgy021001 nanoscience & nanotechnologyAnodeRed shiftSettore ING-IND/23 - Chimica Fisica Applicatachemistry0210 nano-technologydescription
Abstract Anodic films of different thickness (∼30 nm and 70 nm) were grown by anodizing sputtering-deposited Ta-19at% Al to different formation voltages. N incorporation into the anodic films was inducing by performing the anodizing process in ammonium containing solutions. Layered anodic films were prepared by a double formation procedure with a first anodizing step in ammonium biborate solution and second anodizing step in borate buffer solution, or vice versa. Glow Discharge Optical Emission Spectroscopy was employed to show the distribution of N across the oxide. Photoelectrochemical measurements evidenced a red shift of the light absorption threshold due to N incorporation. A model was proposed and tested to model the dependence of quantum yield on photon energy and, thus, to estimate the band gap of the layers for both anodized Ta and Ta-19at% Al.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-05-01 |