High-quality dense ZnO thin films: work function and photo/electrochemical properties

0582298 - ÚFCH JH 2025 RIV DE eng J - Journal Article
Krýsová, Hana - Mansfeldová, Věra - Tarábková, Hana - Písaříková, Aneta - Hubička, Zdeněk - Kavan, Ladislav
High-quality dense ZnO thin films: work function and photo/electrochemical properties.
Journal of Solid State Electrochemistry. (2024). ISSN 1432-8488. E-ISSN 1433-0768
R&D Projects: GA ČR GA22-24138S
Institutional support: RVO:61388955 ; RVO:68378271
Keywords : atomic layer deposition * mott-schottky analysis * doped zno * tio2 * rf * crystalline * growth * oxide * al * Zinc oxide * Mott-Schottky analysis * Kelvin probe * Photoelectrochemistry * Spray pyrolysis * Reactive magnetron sputtering
OECD category: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Impact factor: 2.5, year: 2022
Method of publishing: Open access
https://link.springer.com/article/10.1007/s10008-023-05766-6

Compact ZnO (wurtzite) thin films are prepared on four different substrates by (i) spray pyrolysis or (ii) pulsed reactive magnetron sputtering combined with a radio frequency electron cyclotron wave resonance plasma. Films are characterized by AFM, XRD, Kelvin probe, cyclic voltammetry, electrochemical impedance spectroscopy, and UV photoelectrochemistry. Film morphologies, defect concentrations, crystallite size, and orientation provided specific fingerprints for the electronic structure of ZnO close to the conduction band minimum. Fabricated films are referenced, if relevant, to a model system based on a wurtzite single crystal with either Zn-face or O-face termination. Kelvin probe measurements of the ZnO/air interface distinguished effects of annealing and UV excitation, which are attributed to removal of oxygen vacancies close to the surface. In turn, the work function, at the electrochemical interface, specifically addressed the growth protocol of the ZnO electrodes but not the effects of crystallinity and annealing. Finally, high photocurrents of water oxidation are observed exclusively on virgin films. This effect is then discussed in terms of photocorrosion, and work function changes due to UV light.
Permanent Link: https://hdl.handle.net/11104/0350413