Search results for "Mott–Schottky"

showing 3 items of 3 documents

Semiconducting properties of passive films and corrosion layers on weathering steel

2020

Abstract Anodic films were grown on Weathering Steel by potentiostatic polarization in slightly alkaline solution. The photoelectrochemical results reveal that they are n-type iron oxide with Eg = 2.0 eV. Rust layer grown by atmospheric corrosion are n-type semiconductors with a band gap higher than that estimated for the anodic film attributed to the formation of γ-lepidocrocite. The electrochemical impedance spectra allow to evidence that rust layers have a higher conductivity with respect to anodic films due to the presence of highly doped iron oxide layers. The use of Mott-Schottky theory to model the dependence of oxide capacitance as function of potential is critically discussed.

Materials scienceBand gapGeneral Chemical EngineeringIron oxide02 engineering and technologyWeathering steelengineering.materialConductivity010402 general chemistry01 natural sciencesCorrosionchemistry.chemical_compoundElectrochemistryPolarization (electrochemistry)Band gap Carbon steel EIS Mott–Schottky theory Semiconductorsbusiness.industryDoping021001 nanoscience & nanotechnology0104 chemical sciencesSemiconductorSettore ING-IND/23 - Chimica Fisica ApplicataSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialichemistryChemical engineeringengineering0210 nano-technologybusiness
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Passive and transpassive behaviour of Alloy 31 in a heavy brine LiBr solution

2013

The passive and transpassive behaviour of Alloy 31, a highly alloyed austenitic stainless steel (UNS N08031), has been investigated in a LiBr heavy brine solution (400 g/l) at 25 °C using potentiostatic polarisation combined with electrochemical impedance spectroscopy and Mott–Schottky analysis. The passive film formed on Alloy 31 has been found to be p-type and/or n-type in electronic character, depending on the film formation potential. The thickness of the film formed at potentials within the passive region increases linearly with applied potential. The film formed at transpassive potentials is thinner and more conductive than the film formed within the passive region. These observations…

EISMaterials scienceGeneral Chemical EngineeringPassive filmAlloyMetallurgyMott schottkyengineering.materialApplied potentialINGENIERIA QUIMICAStainless steelDielectric spectroscopyElectroquímicaMott–SchottkyBrineElectrochemistryengineeringAcer CorrosióAustenitic stainless steelElectrical conductorTranspassivityElectrochimica Acta
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Enhancement of photoelectrochemical activity for water splitting by controlling hydrodynamic conditions on titanium anodization

2015

This work studies the electrochemical and photoelectrochemical properties of a new type of TiO2 nanostructure (nanosponge) obtained by means of anodization in a glycerol/water/NH4F electrolyte under controlled hydrodynamic conditions. For this purpose different techniques such as Scanning Electronic Microscopy (SEM), Raman Spectroscopy, Electrochemical Impedance Spectroscopy (EIS) measurements, Mott–Schottky (M−S) analysis and photoelectrochemical water splitting tests under standard AM 1.5 conditions are carried out. The obtained results show that electron–hole separation is facilitated in the TiO2 nanosponge if compared with highly ordered TiO2 nanotube arrays. As a result, nanosponges en…

NanotubeNanostructureMaterials scienceAnalytical chemistryEnergy Engineering and Power Technologychemistry.chemical_elementElectrolyteINGENIERIA QUIMICAsymbols.namesakeElectrochemical Impedance SpectroscopyElectrical and Electronic EngineeringPhysical and Theoretical ChemistryWater splittingTiO2 nanostructuresRenewable Energy Sustainability and the EnvironmentAnodizingTitaniDielectric spectroscopyHydrodynamic conditionsElectroquímicaChemical engineeringchemistrysymbolsWater splittingMott–Schottky analysisAnodizationRaman spectroscopyTitanium
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