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Recently, transparent ultraviolet (UV) photodetectors have gained wide attention for their giant potential in integrated transparent electronics applications. SnO2 films as a common candidate for visible-blind transparent ultraviolet photodetectors have attracted increasing attention. In this work, high-performance visible-blind transparent UV photodetectors based on SnO2 thin film and a SiO2 passivation layer were successfully synthesized by the sol–gel spin coating method for the first time. The obtained SnO2/SiO2 hybrid device has a transmittance of nearly 80% in the visible band at 400–700 nm and demonstrates a high responsivity of 769 mA W−1 and a detection sensitivity of 1.24 × 1014 Jones under UV light illumination. The UV-C/UV-A rejection ratio is greater than 106, indicating that the device has good photo-selectivity. In addition, after the introdution of the SiO2 layer, the response speed is 2 times higher than that of pure SnO2. The presence of the SiO2 layer reduces the exposed area of SnO2, passivates the oxygen vacancies on the surface of SnO2 and inhibits the surface chemical adsorption. The above results provide a new perspective for improving the performance of SnO2 thin film for visible-blind transparent ultraviolet photodetectors. [ABSTRACT FROM AUTHOR]

Flexible energy storage based on ferroelectric capacitors enjoys high power density and rapid respond time, but the polarization fatigue problems limit its long-term reliability. Bi3.15Nd0.85Ti3O12 (BNT) is a lead-free ferroelectric material with fatigue-free properties, which is promising for applications in long-term ferroelectric devices. Nevertheless, the applications of BNT thin films for energy storage are restricted by their poor energy efficiency and low energy density. In this work, flexible BNT thin films with different numbers of SrTiO3 (STO) insert layers are fabricated on flexible mica substrates by an exquisitely designed dual-target pulsed laser deposition process, and the energy storage performances are effectively optimized via interface engineering. By inserting periodic STO dielectric layers with repetition periods of 100, the energy storage density (Wrec) and efficiency (η) are improved to ∼24.26 J cm−3 and ∼71.93%, which are, respectively, increased to 287% and 132% compared with the pure phase BNT thin film. Importantly, the improved Wrec and η can be well maintained under large bending deformation (bending radius as small as r = 4 mm) and within a wide temperature range (25–175 °C), suggesting its good stability and reliability. These results show that the involvement of periodic dielectric layers in BNT thin films can significantly enhance energy storage density and efficiency and effectively promote its applications in future flexible energy storage devices. [ABSTRACT FROM AUTHOR]

Anion doping is an efficient method for modifying the electrical property of the p‐type semiconductor CuI. However, adjustment of the hole density is still challenging. Using sputtering and spin coating techniques, well‐controlled S‐doping of CuI thin films has been realized. The spin‐coated samples present a single (111) out‐of‐plane orientation and very high crystallinity, which is comparable with previously reported epitaxial CuI thin films. The sputtered thin films have advantages in surface morphology and conductivity. Substituting S for I can achieve efficient acceptor doping of CuI for both the physical and chemical growth methods. The highest conductivity of CuI appears at 2.0 at% of S doping, and the doping efficiency is influenced by the self‐compensation effect. [ABSTRACT FROM AUTHOR]

An infrared transparent conductive material is a solution to realize the shielding function of infrared windows against electromagnetic waves, by combining the two characteristics of high transmission and conductivity in infrared wavelengths. Indium-hydroxide-doped (In2O3:H) thin films were prepared by atomic layer deposition method, which can achieve high IR transmission by reducing the carrier concentration on the basis of ensuring the electrical properties. On this basis, the effect of the post-deposition annealing process on the microstructure evolution and optoelectronic properties of In2O3:H thin films was investigated in this paper. It is demonstrated that the carrier mobility after annealing is up to 90 cm2/(V·s), and the transmittance at the 4 μm is about 70%, meanwhile, the carrier concentration after annealing in air atmosphere is reduced to 1019 cm−3, with a transmission rate of up to 83% at 4 μm. The simulations visualize the shielding performance of the annealed In2O3:H thin film against radar electromagnetic waves. It provides a guideline for fabricating lightweight, thin, and multi-functional shielding infrared transparent materials in the key fields of spacecraft and high precision electronics. [ABSTRACT FROM AUTHOR]

Automatic inspection of micro-defects of thin film transistor-liquid crystal display (TFT-LCD) panels is a critical task in LCD manufacturing. To meet the practical demand of online inspection of a one-dimensional (1D) line image captured by the line scan visual system, we propose a robust 1D Fourier reconstruction method with the capability of automatic determination of the period Δx of the periodic pattern of a spatial domain line image and the neighboring length r of the frequency peaks of the corresponding frequency domain line image. Moreover, to alleviate the difficulty in the discrimination between the defects and the non-uniform illumination background, we present an effective way to correct the non-uniform background using robust locally weighted smoothing combined with polynomial curve fitting. As a proof-of-concept, we built a line scan visual system and tested the captured line images. The results reveal that the proposed method is able to correct the non-uniform illumination background in a proper way that does not cause false alarms in defect inspection but also preserves complete information about the defects in terms of the brightness and darkness as well as the shape, indicating its distinct advantage in defect inspection of TFT-LCD panels. [ABSTRACT FROM AUTHOR]

Pharmaceutical contaminants in surface water have raised significant concerns because of their potential ecological risks. In particular, coronavirus disease 2019 (COVID-19)-related pharmaceuticals can be released to surface water and reduce environmental water quality. Therefore, reliable and robust sampling tools are required for monitoring pharmaceuticals. In this study, passive sampling devices of diffusive gradients in thin films (DGTs) were developed for sampling 35 pharmaceuticals in surface waters. The results demonstrated that hydrophilic–lipophilic balance (HLB) was more suitable for DGT-based devices compared with XAD18 and XDA1 resins. For most pharmaceuticals, the performance of the HLB-DGT devices were independent of pH (5.0–9.0), ionic strength (0.001–0.5 M), and flow velocity (0–400 rpm). The HLB-DGT devices exhibited linear pharmaceutical accumulation for 7 days, and time-weighted average concentrations provided by the HLB-DGT were comparable to those measured by conventional grab sampling. Compared to previous studies, we extended DGT monitoring to include three antiviral drugs used for COVID-19 treatment, which may inspire further exploration on identifying the effects of COVID-19 on ecological and human health. [Display omitted] • We broadened the variety of target pharmaceuticals detected by DGT. • Three antiviral COVID-19 drugs were detected by DGT in surface water. • DGT offers trace-level contamination detection at relatively low temperatures. • DGT can be used for monitoring pharmaceuticals instead of conventional grab sampling. [ABSTRACT FROM AUTHOR]

[Display omitted] Gas hydrates have gained great interest in the energy and environmental field as a medium for gas storage and transport, gas separation, and carbon dioxide sequestration. The presence of small doses of surfactants in the aqueous phase has been reported to enhance hydrate formation; however, the underlying mechanisms remain poorly understood. Thus, in situ high-resolution X-ray computed tomography measurements were performed to monitor the upward water migration and the resulting hydrate nucleation and growth. It was found that the presence of hydrate crystals at the gas–liquid–solid contact line triggered the enhanced growth of hydrates on the reactor wall. A time delay was observed between the disappearance of the bulk water reservoir and its transformation into hydrate. The lower interfacial tension between the hydrate surface and the solution facilitated its adsorption onto the reactor wall once a thin film of hydrate nucleated on the solid wall surface. These hydrate layers present on the reactor wall were found to be porous, wherein the porosity decreased with increased subcooling. These fundamental results will be of value in understanding the mechanism of hydrate growth in the presence of surfactants and its potential application in hydrate-based technologies. [ABSTRACT FROM AUTHOR]

• A nanostructure was fabricated on the surface of Ti-Cu alloy. • The nanostructure was composed of TiO 2 , CuO and Cu 2 O. • The surface modified Ti-Cu alloy reduced inflammatory response. Once a biomaterial is implanted, inflammatory response will happen on the implant. Prolonged inflammatory events will decrease the implant success rate. Implants with nanostructured surfaces have been considered as an effective strategy to reduce inflammatory response. A TiO 2 nanostructured surface doped with CuO and Cu 2 O on Ti-Cu alloy was fabricated by NaOH, deionized water and heat treatments. The RAW 264.7 macrophages were used to research the inflammatory on the nanostructured surface. The nanostructure presented excellent cytocompatibility, but reduced inflammatory response by downregulating mRNA expressions of proinflammatory cytokines and secretion of proinflammatory cytokine, implying that the nanostructure might benefit implantation success. [ABSTRACT FROM AUTHOR]

In this paper, the single-doped (Ni-WO 3 and Ti-WO 3) and binary-doped (Ni-Ag-WO 3 and Ti-Ag-WO 3) amorphous WO 3 thin films were respectively prepared on indium-doped tin oxide conductive glass substrates by radio-frequency magnetron sputtering. Among the single-doped WO 3 thin films, the electrochromic (EC) properties of films can be enhanced by the presence of Ni or Ti. However, the low conductivity of WO 3 limits its application in EC devices. A novel approach was proposed to ameliorate this disadvantage which has not been explored, that is, the highly conductive Ag was introduced into WO 3 films with Ni or Ti. The experimental results show that the addition of Ag reduces the charge transfer resistance and shortens the ion diffusion path length, thereby improving the EC response time (Ni-Ag-WO 3 : t b =1.16 s; Ti-Ag-WO 3 : t c =4.14 s), electrochemical active area, and ion diffusion coefficients (Ni-Ag-WO 3 : D a =3.032 × 10−9 cm2/s; Ti-Ag-WO 3 : D c =7.737 × 10−9 cm2/s). Based on these work, the feasibility of Ni-Ag and Ti-Ag binary-doped WO 3 films was confirmed. These discoveries contribute to the exploration of preparing high-performance WO 3 EC films for the practical applications of EC devices such as in automatic anti-glare rearview mirrors. [ABSTRACT FROM AUTHOR]

The effects of post-deposition oxygen annealing temperature on the physical, chemical, and optical properties of gallium oxide (Ga 2 O 3) films were systematically studied in this work. First, Ga 2 O 3 films were deposited on Si (100) substrates by atomic layer deposition (ALD) and then annealed at 500–900 ℃, respectively. Several standard surface analysis methods were used to characterize the Ga 2 O 3 films before and after annealing. X-ray diffraction (XRD) patterns illustrated that the as-deposited amorphous film transitioned to β-phase after annealing at temperatures greater than 600 ℃. Atomic force microscopy (AFM) images showed that the grain size and roughness of the films significantly increased when annealed above 700 ℃. Transmission electron microscopy (TEM) tests presented that the interface microstructure was slightly affected by the annealing process. The effects of the annealing process on optical properties were performed using photoluminescence spectroscopy (PL) and spectroscopic ellipsometry (SE). Moreover, X-ray spectroscopy (XPS) was utilized to extract the oxygen vacancy (V O) concentration, bandgap, and the energy band alignment of Ga 2 O 3. With increasing annealing temperature, it was found that the atomic ratio of O/Ga increased while V O decreased monotonically from 47.4 % to 27.0 %. Density functional theory (DFT) simulation further accounted for energy band shifts resulting from the variation of V O. This study provides a means to achieve high-quality β-Ga 2 O 3 films, highly significant for applications of β-Ga 2 O 3 -based ultraviolet photodetectors and other relevant devices. • The temperature-dependent annealing effect on chemical state, microstructure, and optical properties of Ga 2 O 3 film is systematically studied. • The relationship of the band structure with annealing temperature and oxygen vacancy defects is established. • The energy bandgap of Ga 2 O 3 can be tuned from 4.75 eV to 4.94 eV by controlling the annealing temperature. • The DFT theoretical calculation combined with XPS results gives insight into the effect of oxygen vacancy defects on the properties of the Ga 2 O 3. [ABSTRACT FROM AUTHOR]

Atom passivation with halogen shows the best performance for PbS CQDs optoelectronic application for its short distance and stability via preventing oxidized to CQDs surface. Chlorine is hardly researched for its high activity and low binding energy to Pb. Here, lead halide was used as precursor by surface ligand engineering, introducing halogen during synthesis before ligand exchange and film deposition. Halogen of precursor was proved on the surface of as synthesized CQDs and still passivated on the surface after phase transfer ligand exchange by PbI 2. Mixed halogen surface passivation layer balance the height and width of tunneling barrier between two adjacent CQDs which improving photo detector current and performance. Our works provide Cl doping passivation method but also elucidate understanding of the impact of photo detection performance via mixed halogen passivation. [ABSTRACT FROM AUTHOR]

Incorporation of thermal responsive nanofillers is a promising strategy to induce thermal responsiveness in thin film nanocomposite (TFN) polyamide NF membranes. In this work, thermal responsive zwitterionic nanocapsules (ZN C s) were embedded in the polyamide (PA) active layers to form thermal responsive water transporting channels for thermal responsive nanofiltration performance. The impact from loading level, diameter, cross-linker ratio, and core/shell ratio of ZN C s on the structure, nanofiltration (NF) performance, and thermal responsive sensitivity of TFN membranes were systematically investigated. It was found that ZN C s with the diameter of 100–110 nm, cross-linker ratio of 50 wt% and core/shell ratio of 3:1, and loading level of 0.01% w/v in aqueous phase had induced the highest permeance change slope of 1.04 L m−2 h−1·bar−1 °C−1 (LMHBC) and flux change slope of 6.24 L m−2·h−1·°C −1(LMHC) for ZN C s-TFN membrane, which was 8.7 times higher than that of the pristine TFC-PA NF membranes. The water flux of such ZN C s-TFN membrane increased from 57 L m−2 h−1 (LMH) to 88 LMH at 0.6 MPa from 25 °C to 30 °C without losing its salt rejection rates. [Display omitted] • High thermal-responsiveness NF membranes were developed by embedding thermal responsive zwitterionic nanocapsules (ZN C s). • Embedding ZN C s could increase water flux without sacrificing salt rejections of NF membranes. • Performance of NF membranes could be tuned by the structure parameters of ZN C s. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly crystalline In 2 O 3 films are grown by pulsed reactive magnetron sputtering. • Substrate heating further improves the film crystallinity and conductivity. • 400 °C is the limit for benefiting to obtain the optimum crystallinity of In 2 O 3 films. • The films deposited at 400 °C yield the lowest resistivity of 1.28 × 10-4 Ω⋅cm. • An average transmittance of greater than 80% are also obtained at 400 °C. A transparent conductive oxide (TCO) should have a combination of high electrical conductivity and optical transmission property to fulfill the challenging demands of industrial applications. So far, doped TCOs have been mostly considered to fulfill the technological challenges. In this study, we demonstrate that indium oxide (In 2 O 3) thin films without intentional doping can be deposited with high crystallinity under specific film growth conditions leading to thin films with high mobility, high electrical conductivity, and high transmittance. In 2 O 3 thin films have been deposited by reactive pulsed direct current magnetron sputtering (pulsed DCMS) from an indium target on substrates in a temperature range from room temperature (RT) to 600 °C. Detailed investigations on In 2 O 3 thin films are performed and the film properties such as crystallinity, microstructure, chemical bonding states, electrical and optical properties are revealed. Enhanced plasma density and ionization degree provided by the employed reactive pulsed DCMS and the intentional substrate heating during the thin film deposition give possibility to deposit highly crystalline thin films which are preferentially oriented in (2 2 2) direction. The substrate heating enhances the crystallinity of the grown films up to a certain optimum temperature: 400 °C. When the substrate temperature is above 400 °C, the carrier concentration and mobility decrease due to the grain refinement effect caused by growth competition of grains in different orientations. The films grown at 400 °C indicate the presence of high oxygen vacancy concentrations, which can directly be associated with a high charge carrier concentration despite the lack of intentional doping. The undoped In 2 O 3 films in this study grown at 400 °C show highly promising and competitive electrical properties such as low resistivity of 1.28 × 10-4 Ω⋅cm and the high carrier mobility of 69 cm2/Vs. The average transmittance of the In 2 O 3 films with the highest conductivity is found to be greater than 80% in the visible to the near-infrared spectral region owing to an enhancement in the carrier mobility and an optical bandgap in the range from 3.61 eV to 3.77 eV. [ABSTRACT FROM AUTHOR]

Texture could improve the tribological properties of thin films effectively. The mechanism of surface texture improving tribological performance has been extensively studied. However, the coupling effect of surface texture and interface texture on tribological performances needs to be comprehensively understood. In this work, we fabricated surface/interface textured carbon films. The experimental results proved that the tribological properties of carbon films had a remarkable enhancement after adding surface/interface texture and they were strongly related to the texture parameters. The mechanism of the enhanced performance was discussed based on the promotion of transfer films and the enhancement of film-substrate adhesion strength induced by the surface/interface texture. Finally, a coupling effect of surface/interface texture on the tribological performance was proposed. [Display omitted] • A technique for fabricating controllable surface/interface texture was developed. • Tribological properties were significantly enhanced with optimal texture size. • Coupling effect of surface/interface texture on transfer film and film-substrate adhesion was explored. [ABSTRACT FROM AUTHOR]