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Integration of thin-film oxide piezoelectrics on glass is imperative for the next generation of transparent electronics to attain sensing and actuating functions. However, their crystallization temperature (above 650 °C) is incompatible with most glasses. We developed a flash lamp process for the growth of piezoelectric lead zirconate titanate films. The process enables crystallization on various types of glasses in a few seconds only. The functional properties of these films are comparable to the films processed with standard rapid thermal annealing at 700 °C. A surface haptic device was fabricated with a 1 μm-thick film (piezoelectric e33,f of −5 C m−2). Its ultrasonic surface deflection reached 1.5 μm at 60 V, sufficient for its use in surface rendering applications. This flash lamp annealing process is compatible with large glass sheets and roll-to-roll processing and has the potential to significantly expand the applications of piezoelectric devices on glass. Direct growth of piezoelectric oxides on glass is difficult due to high processing temperatures. Here, the authors demonstrate a flash lamp process for the growth of films on various glasses in a few seconds only. The films have piezoelectric e33,f of −5 C m−2 and can be used in haptic devices. [ABSTRACT FROM AUTHOR]

The atmospheric corrosion behavior of new-type weathering steels (WSs) was comparatively studied, and the effects of Nb and Sb during corrosion were clarified in detail through field exposure and characterization. The results showed that the addition of Nb and Sb played positive roles in corrosion resistance, but there was a clear difference between these two elements. Nb addition slightly improved the rust property of conventional WS but could not inhibit the electrochemical process. In contrast, Sb addition significantly improved the corrosion resistance from the aspects of electrochemistry and rust layer. Compared with only 0.06wt% Nb, the combination of 0.05wt% Sb and 0.06wt% Nb could better optimize the rust structure, accelerate the formation of a high proportion of dense and protective α-FeOOH, repel the invasion of Cl−, and retard the localized acidification at the bottom of the pit. [ABSTRACT FROM AUTHOR]

In this paper, the stress corrosion cracking (SCC) behaviors of X100 pipeline steel are studied in a carbonate/bicarbonate solution with different concentrations of chloride (Cl−) by using slow stress-strain tests, electrochemical measurements, x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The effect of Cl− on the SCC process is discussed based on the change of surface state and the force of crack propagation. The results showed that the SCC susceptibility of the steel increased with the rise of Cl− concentration. Cl− promoted the SCC process by providing a high driving force for crack propagation and accelerating anodic dissolution. Furthermore, Cl− reduced the FeCO3 content in the film on the steel surface, which facilitated the initiation of SCC. [ABSTRACT FROM AUTHOR]

The effect of alternating magnetic field on electrochemical behavior of 316L and TA2 in simulated seawater was studied by potentiodynamic polarization, electrochemical impedance spectra, potentiostatic polarization, and surface morphology topology. Results show that the alternating magnetic field induces convection and enhances mass transport, which promote destruction of the passive film caused by chloride ion and accelerate cations to leave the electrode/solution interface, consequently resulting in dissolution of passive film and metal substrate of 316L. Changes of TA2 induced by magnetic field are quite weak due to superior resistance of TiO2 of the top layer of passive film. [ABSTRACT FROM AUTHOR]

The stress corrosion cracking (SCC) of 2205 duplex stainless steels (DSSs) with different microstructures in simulated sea environments were studied by electrochemical measurements, electron backscattered diffraction and slow strain rate tensile tests. Heat treatments were used to obtain different microstructures. The DSSs were held at 1350 and 850 °C for 30 min and then quenched in the water. The results showed that the DSSs had a higher SCC susceptibility in simulated shallow sea environment than in the simulated deep-sea environment. Electrochemical mechanism of the SCC process was controlled by environment factors (temperature, hydrostatic pressure and dissolved oxygen content). The mechanisms of SCC changed from anodic dissolution in the simulated shallow sea environment to hydrogen embrittlement in the simulated deep-sea environment. Moreover, the quenched DSSs, especially the steel held at 850 °C, were more vulnerable to SCC than as-received steel in the simulated sea environment due to the deterioration of the microstructure. [ABSTRACT FROM AUTHOR]

This study investigated the effect of flowing velocity and impact angle on the fluid-accelerated corrosion (FAC) of X65 pipeline steel in a wet CO2-containing environment by corrosion morphology analysis, electrochemical measurement, and hydromechanical numerical analysis. It has been found that the corrosion behavior was controlled by the ion diffusion rate and shear stress due to the flowing gas. With an increase in the flowing velocity, the pitting corrosion initially decreased and then increased when the flowing velocity exceeded 14 m/s; this increase is caused by the augmentation of shear stress. When the impact angle decreased, the position of serious corrosion gradually moved outwards. [ABSTRACT FROM AUTHOR]

Although InO nanofibers (NFs) are well-known candidates as active materials for next-generation, low-cost electronics, these NF based devices still suffer from high leakage current, insufficient on-off current ratios ( I / I ), and large, negative threshold voltages ( V ), leading to poor device performance, parasitic energy consumption, and rather complicated circuit design. Here, instead of the conventional surface modification of InO NFs, we present a one-step electrospinning process (i.e., without hot-press) to obtain controllable Mg-doped InO NF networks to achieve high-performance enhancement-mode thin-film transistors (TFTs). By simply adjusting the Mg doping concentration, the device performance can be manipulated precisely. For the optimal doping concentration of 2 mol%, the devices exhibit a small V (3.2 V), high saturation current (1.1 × 10 A), large on/off current ratio (>10), and respectable peak carrier mobility (2.04 cm/(V·s)), corresponding to one of the best device performances among all 1D metal-oxide NFs based devices reported so far. When high- κ HfO thin films are employed as the gate dielectric, their electron mobility and V can be further improved to 5.30 cm/(V·s) and 0.9 V, respectively, which demonstrates the promising prospect of these Mg-doped InO NF networks for highperformance, large-scale, and low-power electronics. [ABSTRACT FROM AUTHOR]

Because of their unique physical and chemical properties, one-dimensional (1-D) metal-oxide nanostructures have been extensively applied in the areas of gas sensors, electrochromic devices, nanogenerators, and so on. Solar water-splitting has attracted extensive research interest because hydrogen generated from solar-driven water splitting is a clean, sustainable, and abundant energy source that not only solves the energy crisis, but also protects the environment. In this comprehensive review, the main synthesis methods, properties, and especially prominent applications in solar water splitting of 1-D metal-oxides, including titanium dioxide (TiO), zinc oxide (ZnO), tungsten trioxide (WO), iron oxide (FeO), and copper oxide (CuO) are fully discussed. [ABSTRACT FROM AUTHOR]

Hybrid inorganic-organic heterojunction solar cells (HHSCs) are successfully fabricated using SbS as a light-absorbing semiconductor, TiO nanorods (NRs) as an electron-transport layer, and poly-3 (hexylthiophene) (P3HT) as both a hole conductor and light absorber. The enhanced photo-to-electric conversion performance is expected to (1) enhance optical absorption in the visible light region by SbS and (2) photo-generate highly efficient charge carrier separation at TiO/SbS and SbS/P3HT heterojunction interfaces. The power conversion efficiency (PCE) of HHSCs improves approximately fourfold by inserting the SbS layer, which can be further enhanced about four more times by optimizing the length of TiO nanorod arrays (NRAs). Finally, the mechanism to illustrate the effect of the length of TiO NRs on the PCE is discussed. This leads to a theory for achieving high-efficiency inorganic-organic solar cells. [ABSTRACT FROM AUTHOR]

Although significant developments have been made in the low-concentration formaldehyde monitoring in indoor air by using gas sensors, they still suffer from insufficient performance for achieving ppb-level detection. In this work, <100> oriented Si nanowires (SiNWs) with high specific surface area were prepared via metal-assisted chemical etching method (MACE), and then were uniformly coated with graphene oxide (GO) followed by the subsequent reductive process in H2/Ar atmosphere at 800 °C to obtain reduced graphene oxide (RGO). The RGO coating (RGO@n-SiNWs) obviously enhances SiNWs sensitivity to low-concentration formaldehyde, benefiting from the increased specific surface area, the sensitization effect of RGO, and the formation of p-n junction between SiNWs and RGO. Specifically, RGO@n-SiNWs exhibits a high response of 6.4 to 10 ppm formaldehyde at 300 °C, which is about 2.6 times higher than that of pristine SiNWs (~ 2.5). Furthermore, the RGO@n-SiNWs show a high response of 2.4 to 0.1 ppm formaldehyde which is the largest permissive concentration in indoor air, a low detection limit of 35 ppb obtained by non-linear fitting, and fast response/recovery times of 30 and 10 s. In the meanwhile, the sensor also shows high selectivity over other typical interfering gases such as ethanol, acetone, ammonia, methanol, xylene, and toluene, and shows a high stability over a measurement period of 6 days. These results enable the highly sensitive, selective, and stable detection of low-concentration formaldehyde to guarantee safety of indoor environment. [ABSTRACT FROM AUTHOR]

The morphologies and microstructures of Au-catalyzed InGaAs nanowires (NWs) prepared by a two-step solid-source chemical vapor deposition (CVD) method were systematically investigated using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The detailed structural characterization and statistical analysis reveal that two specific morphologies are dominant in InGaAs NWs, a zigzag surface morphology and a smooth surface morphology. The zigzag morphology results from the periodic existence of twining structures, and the smooth morphology results from a lack of twining structures. HRTEM images and energy-dispersive X-ray spectroscopy (EDX) indicate that the catalyst heads have two structures, Au4In and AuIn2, which produce InGaAs NWs in a cubic phase crystalline form. The growth mechanism of the InGaAs NWs begins with Au nanoparticles melting into small spheres. In atoms are diffused into the Au spheres to form an Au-In alloy. When the concentration of In inside the alloy reaches its saturation point, the In precipitate reacts with Ga and As atoms to form InGaAs at the interface between the catalyst and substrate. Once the InGaAs compound forms, additional precipitation and reactions only occur at the interface of the InGaAs and the catalyst. These results provide a fundamental understanding of the InGaAs NW growth process which is critical to the formation of high-quality InGaAs NWs for various device applications. [ABSTRACT FROM AUTHOR]