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Un-doped VO2, tungsten (W)-doped VO2, and W/Zn co-doped VO2 thin films were successfully prepared by two DC magnetron sources and co-sputtered at a substrate temperature of 425°C onto soda lime glass substrates. The aim was to find whether co-doping of VO2 films with W and Zn could decrease the transition temperature and increase both luminous transmittance and solar transmittance modulation (ΔTsol) of VO2 -based thin films. The thin films were characterized by x-ray diffraction, atomic force microscopy, Rutherford backscattering spectroscopy, the two-point probe technique, Hall effect measurement system, and a PerkinElmer Lambda 1050+ UV/VIS/NIR) spectrometer. This work revealed that a controlled amount of Zn in the W-doped VO2 films showed solar transmittance modulation of 4%. It further improves the luminous transmittance to ~ 46%, lowering the phase transition temperature to below 27°C, compared to un-doped VO2 and W-doped VO2 thin films at 64.8°C and 44°C, respectively. These results show that the combined effect of W and Zn doping on VO2 films has the potential to make the films useful for smart window applications. [ABSTRACT FROM AUTHOR]

Noble gas ion sputtering combined with Auger electron spectroscopy (AES) analysis has been applied extensively for elemental composition depth profiling of the target materials. Such depth profiles have been used widely not only for elemental composition analysis but also for extracting the sputtering yields of the target materials. Despite a large number of publications on sputtering yields there are only a small number of reports (in literature) on the measured sputtering yields of indium compounds. Indium is used to dope semiconductors for electronic devices (transistor) and thin film solar cells. In order to obtain accurate depth information (for indium thin films) with Ar+ ion profiling, it is essential to have reliable sputtering yields for the In metal. In this study, the argon ion sputtering yields of indium films are reported for a range of low ion beam energies (0.5-4.0 keV). The indium films (106 nm) were deposited on SiO2 substrates under vacuum by electron beam evaporation. The films were subjected to Ar+ ion sputtering combined with AES analysis to obtain the depth profiles, which were used to extract the sputtering yield values. The obtained sputtering yield values are in the range of 2 to 6 atoms/ions for Ar+ ion beam energies in the range of 0.5-4.0 keV, respectively. The Monte Carlo simulation code, Stopping and Range of Ions in Materials (SRIM) were used to simulate the Ar+ ion bombardment of the indium film and to obtain the surface sputtering yields and influences the structures as deposited and the corresponding activities induced. These were also calculated using a semi-empirical formula developed for such predictions. The sputtering yields obtained from SRIM and the semi-empirical formula are in agreement with the experimental values. [ABSTRACT FROM AUTHOR]

The influence of 150 keV argon ions at fluences in the range of 1 × 10 12 -1 × 10 16 ions/cm 2 on the stability of the multilayer stack Pd/Zr/Pd/Ti/Pd thin films system, deposited on Ti and Ti 6 Al 4 V substrates, under thermal annealing in an H 2 environment was investigated. For samples deposited on Ti substrate, RBS revealed structural instability that increases with fluence. This is evidenced by a decrease in the intensity of layers accompanied by increased consumption of the Pd layers. This effect led to the initial individual layers becoming one compound layer and the formation of a new Ti-O-Pd layer, indicating a complete intermixing of layers at 1 × 10 16 ions/cm 2 . However, for the samples deposited on Ti 6 Al 4 V substrate, the Pd layers could still be identified and resolved, indicating an incomplete intermixing of layers. XRD revealed the structural transformation of layers via an intermixing process resulting in the formation of two new phases, TiH 2 and ZrH 2 , classified as face-centered tetragonal (FCT) crystal structures. ERDA confirmed the presence of hydrides in the system indicating the absorption of H into the system to a maximum H amount of ∼5.2 at.%, at higher fluence, for the same multilayer stack deposited on both substrates., Competing Interests: Dear Editor, Authors declare that this work is not a duplicate of any study conducted before nor any part of the work published or submitted in any journal. The authors declare that they have no conflict of interest in the publication of this article., (© 2024 The Authors.)

In this article, we used a two-step chemical vapor deposition (CVD) method to synthesize methylammonium lead-tin triiodide perovskite films, MAPb 1-x Sn x I 3 , with x varying from 0 to 1. We successfully controlled the concentration of Sn in the perovskite films and used Rutherford backscattering spectroscopy (RBS) to quantify the composition of the precursor films for conversion into perovskite films. According to the RBS results, increasing the SnCl 2 source amount in the reaction chamber translate into an increase in Sn concentration in the films. The crystal structure and the optical properties of perovskite films were examined by X-ray diffraction (XRD) and UV-Vis spectrometry. All the perovskite films depicted similar XRD patterns corresponding to a tetragonal structure with I4cm space group despite the precursor films having different crystal structures. The increasing concentration of Sn in the perovskite films linearly decreased the unit volume from about 988.4 Å 3 for MAPbI 3 to about 983.3 Å 3 for MAPb 0 . 39 Sn 0 . 61 I 3 , which consequently influenced the optical properties of the films manifested by the decrease in energy bandgap (E g ) and an increase in the disorder in the band gap. The SEM micrographs depicted improvements in the grain size (0.3-1 µm) and surface coverage of the perovskite films compared with the precursor films.

Cadmium (Cd) is frequently used in various industrial applications and is a ubiquitous environmental toxicant, also present in tobacco smoke. An important route of exposure is the circulatory system whereas blood vessels are considered to be main stream organs of Cd toxicity. Our previous results indicate that cadmium chloride (CdCl2) affects mean arterial blood pressure in hypertensive rats. We hypothesized that Cd alters the intracellular calcium transient mechanism, by cadmium-induced stimulation of MAPKs (ERK 1 & 2) which is mediated partially through calcium-dependent PKC mechanism. To investigate this hypothesis, we exposed primary cultures of vascular smooth muscle cells (VSMCs) from wistar kyoto (WKY) and spontaneously hypertensive rats (SHR) to increased concentrations of CdCl2 on cell viability, expression of mitogen-activated protein kinases (MAPKs/ERK 1 & 2), and protein kinase C (PKC) which are activated by Cd in several cell types. The results from these studies indicate that CdCl2 decreased cell viability of both SHR and WKY VSMCs in a concentration dependent-manner. Viability of both cell types decreased 33+/-5.3 (SHR) and 39+/-2.3% (WKY) when exposed to 1 microM CdCl2, whereas, 8 and 16 microM reduced viability by 66+/-3.1 and 62+/-4.5% in SHR cells. CdCl2 increased ERK 1 & 2 in a biphasic manner with maximum increase occurring when cells are exposed to 1 and 4 muM in SHR VSMCs, whereas, a reduction in ERK 1 and 2 is observed when WKY cells are treated with 2 microM. The results also indicate that CdCl2 increased PKC a/Beta in both SHR and WKY VSMCs with a greater increase in expression in SHR VSMCs. In addition, the [Ca2+]i chelator, BAPTA, suppressed the CdCl2 effect, whereas, the PKC inhibitor, GF109203X, reduced the CdCl2 induced-effect on PKC expression. The present studies support the hypothesis that Cd can be a risk factor of hypertension through dysfunction of vascular smooth muscle cells under certain conditions.