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Graphene platelets (electrically conductive 2D filler) and rubber nanoparticles (0D soft filler) can work together to develop electrically conductive and toughened epoxy composite adhesives. In this study, complementing effect between graphene platelets (GnPs) and rubber nanoparticles (RnPs) within an epoxy matrix is reported. In the 3‐phase composite adhesive, the 2D graphene platelets form global conductive network and rubber nanoparticles provide a viscoelastic phase inside the epoxy, both complementing each other to develop electrically conductive and toughened epoxy composite adhesives. Fracture toughness (K1c) and critical strain energy release rate (G1c) of the epoxy were augmented by 422% and 872%, respectively by adding 1 wt% RnPs and it recorded electrical percolation threshold at 0.78 vol% GnP. Also, the Young's modulus and strength of epoxy/1 wt% RnP composite were promoted from 1.57 to 2.32 GPa when 1 wt% GnP is added. Scanning electron microscopy analysis was conducted to investigate the toughening mechanism of epoxy/RnP/GnP and epoxy/GnP composites. Lap shear strength tests on epoxy composite adhesives confirm the reinforcement effect of GnPs and toughness effect of RnPs. [ABSTRACT FROM AUTHOR]

High quality CdZnTe films were prepared on GaN substrates by a close-spaced sublimation method and ZnTe transition layers were introduced to decrease the lattice mismatch between substrates and CdZnTe films for the first time. The morphology and structure of multilayer films were measured by x-ray diffraction and scanning electron microscopy. The crystalline quality of CdZnTe films based on ZnTe transition layers is obviously optimized and the best full width at half maximum and grain size of CdZnTe films are 0.149° and 10.4 μm, respectively. A surface defect analysis of multilayer films was studied by x-ray photoelectron spectroscopy and low temperature photoluminescence, which indicated that the introduction of ZnTe transition layer can reduce the Cd vacancy ratio of CdZnTe films from 22.9% to 13.3%. It is also found that the electrical properties of GaN/ZnTe/CdZnTe multilayer films show a similar PN junction effect and the best photo-dark current ratio reaches 38.8. The responsivity of multilayer films under 254 nm light is about 69.1 times more than that to 400 nm, which improves the detection of CdZnTe films in the solar-blind region effectively. [ABSTRACT FROM AUTHOR]

SnS nanobelt thin films were deposited on glass substrates in acidic solution by chemical bath deposition (CBD) method. The belt-like morphologies of as-deposited SnS thin films were characterized by scanning electron microscope (SEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) and Raman measurements were carried out to confirm the crystal structures and phase purities of SnS nanobelt thin films. The morphologies and phase purities of SnS thin films were influenced greatly by the tin and sulfur precursors. The bandgaps of SnS nanobelts were determined to be 1.39–1.41 eV by UV–vis absorption and photoluminescence (PL) spectra. Current-voltage ((I V)) and current-time ((I-T)) characteristics were studied to demonstrate the photoelectric performances of SnS nanobelt thin films. [ABSTRACT FROM AUTHOR]

• SnS nanotubes were firstly deposited by electrodeposition method. • The morphologies of SnS nanotubes were modulated by deposition potentials. • Photo-electronic properties of SnS nanotubes were investigated. In this paper, SnS nanotubes are firstly prepared in acidic solution by template free electrodeposition method at room temperature. The morphological evolution and photoelectrochemical properties of SnS nanotubes are investigated. X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) and Raman spectra measurements examine the phase purities of deposited SnS thin films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations indicate morphological properties of SnS nanotubes. The band-gap of SnS nanotubes is confirmed by UV–Vis-NIR diffuse reflection spectra. The photoelectrochemical measurements show that the photocurrent density of FTO/SnS nanotubes is about 31 μA/cm2 and maximum IPCE value of SnS nanotubes is 7.4%. [ABSTRACT FROM AUTHOR]

Front-side illuminated CdS quantum dots (QDs) sensitized solar cells (QDSSCs) based on TiO nanotube arrays (TNTAs) were fabricated. The free-standing TNTAs (f-TNTAs) membranes were obtained from anodic oxidized Ti foils by self-detaching technique and then transferred to FTO glass substrates to form photoanodes. CdS QDs were loaded on TNTAs by sequential chemical bath deposition approach. Scanning electron microscope (SEM) results indicated that the morphology and structure of TNTAs membranes did not change in detaching and transferring process. Power conversion efficiency of the devices from the front-side illumination mode is 1.47 %, which is much higher than that (0.34 %) of the back-side illumination mode owing to the markedly improved light absorption. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, Cu2FeSnSe4 (CFTSe) sheets were synthesized by a facile solvothermal method for the first time. The structure, morphology, chemical composition and optical properties of the as-synthesized CFTSe sheets were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and UV–vis spectrophotometry. The average particle sizes of the sheets increase with the increasing of the reaction times and temperatures. The band gap of 1.12eV estimated from the UV–vis absorption spectra indicated its suitability for application as absorption layers of thin film solar cells. [Copyright &y& Elsevier]

Abstract: ZnS thin films were deposited from different zinc salts by chemical bath deposition (CBD). Structural, morphological and optical characterizations were performed using different methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectra. The particle sizes of as-deposited ZnS thin films were calculated to be about 12.5–15.5nm and the crystal qualities were improved after annealed at 500 °C in Ar/H2S (5%) atmosphere. Optical absorption measurements indicated that the band gaps of ZnS thin films were in the range of 3.66–3.83eV and they decreased with the increasing of particle sizes. ZnCl2 was found to the best precursor due to the higher crystal quality and compact surface of deposited ZnS thin films. [Copyright &y& Elsevier]

Abstract: Quaternary Cu2CdSnS4 nanoparticles, which are useful for the photovoltaic applications, were successfully synthesized by using a simple solvothermal route. Slightly polydispersed nanoparticles were obtained at temperature of 180°C, analyzed by transmission electron microscopy (TEM). The cernyite structured Cu2CdSnS4 nanoparticles were confirmed by X-ray diffraction (XRD). The morphology and the stoichiometric ratio of the nanoparticles were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The chemical states of the elements in the nanoparticles were analyzed by high-resolution X-ray photoelectron spectroscopy (XPS). The band gap of the as-synthesized Cu2CdSnS4 nanoparticles was determined by UV–Vis absorption spectra measurement. [Copyright &y& Elsevier]

In this paper, SnS nanorods were first prepared in an acidic solution by adjusting the amounts of tri-sodium citrate at room temperature using template-free electro-deposition method. The morphological characteristics and photoelectrochemical (PEC) properties of SnS nanorods thin films were investigated. The phase purity properties of deposited SnS thin films were analyzed by X-ray diffraction (XRD), energy disperse spectroscopy (EDS) and Raman spectra measurements. The morphological characteristics of SnS nanorods were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The band-gaps of SnS thin films were confirmed by UV–Vis–NIR diffuse reflectance spectrum. The PEC characterizations indicated that the photocurrent density of SnS nanorods thin films was about 46 μA/cm2 and the maximum IPCE value of SnS nanorods thin films was 9.3%. The fabrication of FTO/SnS (nanorods)/CdS/TiO 2 /Pt photoelectrode improved the PEC performances of SnS nanorods thin films greatly. The photocurrent density of FTO/SnS (nanorods)/CdS/TiO 2 /Pt reached 0.59 mA/cm2, and the maximum IPCE value of FTO/SnS (nanorods)/CdS/TiO 2 /Pt achieved 27.1%. Image 1 • Template-free electrodeposited SnS nanorods were firstly reported. • The amount of tri-sodium citrate determines the morphological evolution of SnS nanorods. • PEC properties of SnS nanorods were greatly enhanced by FTO/SnS/CdS/TiO 2 /Pt photoelectrode. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the linear attenuation range of electron transmission through film specimens and its dependence on the electron energy, the acceptance half-angle of a detector or an objective aperture, and specimen properties, in the scanning transmission electron microscope (STEM) and the conventional transmission electron microscope (TEM). Electron transmission in the bright-field mode was calculated by the Monte Carlo simulation of electron scattering, and its range of the linear attenuation in film thickness was then determined by a linear least squares fit. The corresponding linear thickness range was shown to increase with the electron energy and the acceptance half-angle, although it decreased with the increase in the atomic number of specimen materials. Under the condition of a 300kV STEM or a 3MV ultra-high voltage electron microscope (ultra-HVEM), the linear attenuation range could extend to several microns for light specimen materials, and this was validated by experimental data in the ultra-HVEM. The presented results can be helpful for accurately measuring the specimen thickness or mass from electron transmission, and estimating the deviation of electron transmission from linearity when tilting a specimen in electron tomography. [ABSTRACT FROM AUTHOR]

Abstract AlN ceramic substrates (c-AlN), with excellent thermal conductivity, were used to deposit high-quality polycrystalline CdZnTe (CZT) thick films for the first time. Meanwhile, AlN transition layers, made by magnetron sputtering method, have been introduced and annealed to modulate the interface properties of CZT/c-AlN composite structures for UV photodetectors. The relationship between the structure as well as performance of CZT films and the anneal temperature of AlN transition layers was studied by SEM, XRD, EDS, UV–vis spectra, XPS and current–voltage (I-V) characteristic. The CZT films deposited on the AlN transition layer annealed at 1200 °C have the best properties, with the full width at half maximum (FWHM) and leakage current of 0.163°and 2.15 × 10−9 A, respectively. The interface regulation can effectively promote the crystallinity of CZT films and lead to optimum UV detection performance of CZT/AlN composite structures. Highlights • Polycrystalline AlN was first used as the substrates for CdZnTe thick films. • High-quality CdZnTe thick films on AlN substrates were prepared successfully by close-spaced sublimation method. • Interface regulation was applied to optimize the ultraviolet light response capability of CdZnTe films. [ABSTRACT FROM AUTHOR]

Here we prepare a composite of tungsten oxide films/porous silicon (WO 3 /PS) hybrid structure synthesized by electrochemical deposition of WO 3 films onto p-type PS with subsequent annealing process in air. The obtained WO 3 /PS products were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy (RS). The gas-sensing properties of WO 3 /PS composite to NO 2 ranging from room temperature (RT, ∼25 °C) to 200 °C were studied. The result indicated that all the WO 3 /PS gas sensors showed typical p-type semiconductor behavior and had an optimal working temperature of RT. Furthermore, compared with PS, the proper deposited WO 3 /PS composite exhibited a higher gas response, shorter response-recovery time, good repeatability and selectivity toward NO 2 gas at RT. This improvement probably owing to the heterojunction effect and its unique microstructure properties. In addition, the possible NO 2 -sensing mechanisms were also discussed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: WO3 nanocrystals have been prepared by a sol–gel route and characterized by X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy. The experimental results show that WO3 nanocrystals have a high crystallographic quality and a good dispersivity. The particles’ sizes are in the range of 25–100nm. The fabricated WO3 nanocrystal-based sensors have an excellent sensitivity and selectivity to acetone, and display a rapid response and recovery characteristics. The developed sensors exhibit a detection limit down to 0.05ppm at 300°C, rendering a promising application in noninvasive diagnosis of diabetes. The response mechanism of the WO3 nanocrystal sensor to low concentration of acetone has been discussed based on the depletion layer model. [Copyright &y& Elsevier]

• CZT micro pillar films have been deposited by CSS method. • The morphologies of CZT micro pillar films were modulated by deposition times. • Photo-electronic properties of CZT micro pillar films were investigated. CdZnTe (CZT) micro pillar films with cubic zinc blend phase have been deposited on single layer graphene coated quartz substrate by close-spaced sublimation technique. Structural and phase purities of deposited micro pillar CZT films were investigated using X-ray diffraction and Raman spectroscopy. Scanning electron microscopy characterizations indicated that the diameters of CZT micro pillars were about 5 µm and their lengths were close to 57 µm. The band-gap of CZT micro pillar films was about 1.53 eV, which was confirmed by UV–Vis–NIR diffuse reflection spectra and PL spectra. The structure of Au/BGZO/CZT/graphene/quartz was fabricated to study its optoelectronic properties. Under the illumination of AM 1.5, CZT micro pillar films had good photo response, which indicated their great potential in the application of optoelectronic devices. [ABSTRACT FROM AUTHOR]