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Tin monosulfide (SnS) is a promising absorber layer material in solar cell devices. In addition to its outstanding electrical and optical properties, SnS does not contain rare heavy-metal atoms. Thus, many researchers have focused on fabricating highly efficient SnS-based solar cell devices. However, the effect H2 annealing on thermally evaporated SnS thin films and their transfer characteristics with various metals have not been thoroughly studied yet. In this paper, SnS was deposited by thermal evaporation and annealed in a H2 gas ambient at 400 °C. X-ray diffraction (XRD), scanning electron microscopy, Hall measurements, and Rutherford backscattering spectrometry revealed that our SnS thin films were single-phase with enhanced physical and electrical properties. Furthermore, the electrical band structure of SnS was investigated by UV-visible and ultraviolet photoelectron spectroscopy analyses to predict the electrical band alignment when in contact with Ti, W, and Mo electrodes. XRD and atomic force microscopy analysis confirmed that SnS was well grown on these metal electrodes. Finally, SnS with Mo electrodes showed the most conductive transfer characteristics.

Conduction band offset (CBO) is an important aspect in the development of SnS-based solar cells. Studies on buffer layers are needed to obtain a CBO that matches the SnS absorber layer. Zn(O,S) is a promising cadmium sulfide replacement for a thin film solar cell buffer layer due to its non-toxicity and large band gap, and its film characteristics can be optimized by adjusting the oxygen and sulfur ratio. However, very few studies have been conducted on processed Zn(O,S) film’s electronic band structure, and the absence is more serious for the case of atomic layer deposition (ALD) method. In this study, we deposited Zn(O,S) films with various ZnO/ZnS cycle ratios using the ALD supercycle method and identified their film characteristics and electronic band structures. Results showed that the Zn(O,S) films had high concentrations of ZnS compared to the ZnS cycle fraction. Mixing the ZnO and ZnS cycles reduced the film’s crystallinity and affected the Zn(O,S) films characteristics. Further, the electronic band structures were identified using UV–vis and UPS analysis. The Zn(O,S) films using 14:1 and 19:1 ZnO/ZnS cycle ratios showed an ideal flat CBO with SnS absorber.

We demonstrate the polyol synthesis of ultrathin Ag nanowires with diameters of 20 nm and an aspect ratio as high as ∼1000 under high-pressure conditions. The increase in pressure increases density and enhances solubility, making the reactive solution rapidly reach super-saturation and increase the nucleation rate to effect a near-instantaneous formation of Ag nuclei. Clearly, the particle size was small at high pressure and an increase in pressure promoted the formation of small-size Ag seed-particles and small diameter wires. As a result, the Ag nanostructures in this study were initially formed as Ag seed particles with a diameter of 20 nm and subsequently grew into well-defined Ag nanowires with a uniform and narrow diameter distribution in the range of 16–22 nm, with a long dimension of up to 20 μm. Fabrication of random networks of the 20 nm diameter Ag nanowires synthesized lead to the fabrication of flexible transparent electrodes with excellent optoelectronic performance, with a sheet resistance of 30 Ω sq−1 and 94% transmittance with a very low haze value of ≤1.0%, making them suitable for electronic display applications.

We have developed highly transparent and electrically conductive hybrid-gel films based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and thin silver nanowires (Ag NWs) with diameters of 20 nm. Ionic gels based on PEDOT:PSS are ionic conductors consisting of anionic PSS and cationic PEDOT. Ag NWs were combined with the conductive PEDOT:PSS chains to assemble electrically conductive gels. The hybrid-gel films were created with a structure that incorporates Ag NWs into the conductive PEDOT chain matrix. We found that the conductivity significantly increased with Ag NW content. The optimized Ag NW-PEDOT:PSS hybrid-gel films exhibited excellent performance with a high transmittance of 92% and a small haze of 1.1% at a low sheet resistance of 20 Ω sq−1, and good mechanical flexibility. Because of the high-performance, it is believed that the Ag NW-PEDOT:PSS hybrid-gel electrodes are highly suitable for practical use in flexible electronics.

The current requirement for expensive laboratory equipment and highly trained personnel highlights the critical need for simple, low cost technologies capable of point-of-care (POC) clinical detection, especially in resource-limited regions. In this report, we propose an innovative, ultra low-cost, plastic-based blood diagnostic platform for POC detection that requires only a minute volume (

Tin disulfide (SnS2) has emerged as a promising two-dimensional (2D) material due to its excellent electrical and optical properties. However, research into 2D SnS2 has mainly focused on its synthesis procedures and applications; its stability to humidity and temperature has yet to be studied. In this work, 2D SnS2 thin films were grown by atomic layer deposition (ALD) and characterized by various tools, such as X-ray diffraction, Raman analysis, and transmission electron spectroscopy. Characterization reveals that ALD-grown SnS2 thin films are a high-quality 2D material. After characterization, a four-inch-wafer-scale uniformity test was performed by Raman analysis. Owing to the quality, large-area growth enabled by the ALD process, 98.72% uniformity was obtained. Finally, we calculated the thermodynamic equations for possible reactions between SnS2 and H2O to theoretically presurmise the oxidation of SnS2 during accelerated humidity and temperature testing. After the accelerated humidity and temperature test, X-ray diffraction, Raman analysis, and Auger electron spectroscopy were performed to check whether SnS2 was oxidized or not. Our data revealed that 2D SnS2 thin films were stable at humid conditions.