Photoluminescence of ZnO:Eu3+ and ZnO:Tb3+ coatings formed by plasma electrolytic oxidation of pure zinc substrate

摘要: Abstract Eu3+ and Tb3+ doped ZnO optical coatings were formed by the Plasma Electrolytic Oxidation (PEO) method from pure Zn sheet, with various dopant concentrations. The morphologies show no significant change introduced or their concentrations, typical appearance of PEO coatings. All elements are uniformly distributed, concentration incorporated dopants is related to concentrations Eu2O3 Tb4O7 particles added basic electrolyte. Wurtzite structure was identified in all samples, induced dopants. Under 260 nm excitation emits broad-band visible region attributed oxygen interstitial defects vacancies. Photoluminescence (PL) ZnO:X3+ (X = Eu, Tb) a sum PL 4f–4f emissions. most effectively excited charge-transfer band 4f5d levels, respectively. By increasing broad decreases favor transitions, an indication energy transfer. ZnO:Eu3+ spectra dominated hypersensitive 5D0→7F2 transition. ions highly asymmetric environment. emission at 541 nm intense ZnO:Tb3+. Judd-Ofelt intensity parameters rise concentration, up Ω2 = 7.8·10−42 cm2 Ω4 = 4.4·10−42 cm2. Radiative lifetime 5D0 level drops 1.12 ms. Chromaticity varies only when samples irradiated UV light, white orange-red green for under 394 nm 464 nm irradiation gives 99.5% color-purity.