Nanostructured ZnO and CuI Thin Films on Poly(Ethylene Terephthalate) Tapes for UV-Shielding Applications

Abstract

In this work, we study a suitability for protection against terrestrial ultraviolet part of the solar spectrum of undoped and doped by indium zinc oxide thin nanostructured films, ZnO and ZnO:In, respectively, and cuprous iodide (CuI) films obtained via Successive Ionic Layer Adsorption and Reaction (SILAR) techniques on the lightweight low cost poly(ethylene terephthalate) (PET) flexible substrates. The film morphology is observed by scanning electron microscopy (SEM). Chemical compositions of the films are investigated by X-ray fluorescence (XRF) microanalysis. To research crystal structure we used X-ray diffraction (XRD) method. The UV-protection ability of the nanostructured thin films, PET tapes and samples consisting of the PET substrates and the films deposited on them by the SILAR method has been evaluated on the base of their optical properties in accordance with an international standard ISO 2443:2012(E) "Determination of sunscreen UVA photoprotection in vitro". According to the research, nanostructured ZnO, ZnO:In and CuI thin films made by the cheap, affordable, and suitable for mass production SILAR method on thin flexible cheap PET substrates have been proposed as a new material for UV-shielding applications. In accordance with an international standard ISO 2443:2012(E), UV-protection ability of the samples consisting of the PET substrates and the films deposited on them by the SILAR method fits the category "excellent" (50+). The best low cost flexible and lightweight UV shielding material turned out to be that consisted from ZnO:In film and PET substrate, the sun protection factor of which equals 157.

Copper-Enriched Nanostructured Conductive Thermoelectric Copper(I) Iodide Films Obtained by Chemical Solution Deposition on Flexible Substrates

“…It is important that XRF spectra of CuI/PI and CuI/PET samples contain quite a lot of sulfur atoms. The presence of sulfur is a distinctive feature of CuI films obtained by the SILAR method [9,10], since the solution of the cationic precursor contains a chemically unstable thiosulfate ion. According to [4,5], the acceptor impurity S can replace iodine and iodine vacancies and thereby increase the conductivity of CuI.…”

“…The advantage of chemical solution deposition is the easy introduction of foreign atoms, which is convenient and efficient for doping [5]. In our earlier works [9,10], we found that CuI films obtained by the SILAR method on various substrates are enriched in copper, but contain sulfur and possible oxygen, which enter them from aqueous precursor solutions. The aim of this work is to study the morphology, chemical composition, crystal structure, and charge transport in nanostructured conducting thermoelectric copper(I) iodide films obtained by the SILAR method to create flexible thermoelectric materials.…”

“…This creates obstacles for their semiconductor applications, especially for flexible electronics and thermoelectrics [5]. In contrast, the chemical solution deposition process Successive Ionic Layer Adsorption and Reaction (SILAR) does not require annealing after deposition [6,9,10], which makes it possible to obtain conductive thermoelectric copper(I) iodide films on various rigid plates or flexible plastic substrates.…”

Copper(I) Iodide Thin Films: Deposition Methods and Hole-Transporting Performance

“…The results indicated that the UV-protection capacity of CuI films on NC substrates falls within the "excellent" category, with sun protection factors reaching up to 9211 for the finest CuI film produced via the SILAR method. Additionally, nanostructured ZnO and CuI thin films on poly(ethylene terephthalate) tapes demonstrated effective UV-shielding applications [72].…”

Conditions for the Synthesis of Zinc Oxide Nanostructures from the Destruction Products of Overvoltage Nanosecond Discharge Between Zinc Electrodes in Oxygen Under Ultraviolet Irradiation of the Substrate

“…Оксид цинку -це прямозонний напівпровідник з шириною забороненої зони близько 3,37 еВ та енергією зв'язку екситону 60 меВ). Він є перспективним для використання як матеріял для виготовлення прозорих контактів і деяких інших важливих застосувань [1][2][3], фотоприймачів [4], світлодіод [5]. Зокрема, в [2] було встановлено придатність наноструктурованих тонких плівок оксиду Цинку для захисту від земної ультрафіолетової частини сонячного спектру, одержаних хемічним методом на недорогих гнучких підкладинках, а у праці [3] наведено результати дослідження наночастинок оксиду Цинку, активованих гамма випроміненням, які показали, що в структурі ZnO відсутні істотні зміни, і вони можуть бути використані для лікування раку.…”