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In this article, we have developed an amorphous CuNiSnO (a-CNTO), which is a p-type amorphous oxide semiconductor (AOS). The a-CNTO thin films were deposited by the pulsed laser deposition method, having high amorphous quality with a rather smooth surface. The a-CNTO films grown at 100 °C exhibited the smoothest surface (root-mean-square roughness of 0.25 nm), highest visible transparency (~85%), and most favorable p-type conductivity (hole concentration of ~1015 cm−3), which are very suitable for electronic device fabrication. Thus, the obtained p-type a-CNTO thin-film transistors (TFTs) have an ON-to- OFF current ratio of $\sim 1.2\times 10^{{5}}$ , the threshold voltage of −2.3 V, the field-effect mobility of 1.37 cm2/Vs, and subthreshold swing of 0.70 V/decade. As a new kind of p-type AOS, the achievement of the p-type a-CNTO TFTs and the low-temperature processes may open the door for practical applications in transparent and flexible electronics.

Memristors based on amorphous oxide semiconductors (AOSs) have attracted considerable attention recently. Here we present the study of amorphous ZnSnO (a-ZTO) memristors. The a-ZTO memristors were fabricated with Al layers as the bottom and top electrodes. The a-ZTO thin films, deposited by pulsed laser deposition, could be formed on the Al layer uniformly, and the Al layers were effective electrodes for a-ZTO memristors. It was verified that the a-ZTO memristors had obvious resistive switching (RS) behaviors, with a high ratio (∼103) of high-resistance and low-resistance states. Almost the same current-voltage curves were observed for five cycles, revealing the stable and reliable nature of devices. Our study demonstrated the a-ZTO memristors is a potential candidate to produce high-quality resistive random-access memories, which may open a path to applications of memristors based on indium-free AOSs.

Ultrathin amorphous InZnO ( ${a}$ -IZO) films and the corresponding ultrathin-film transistors (UTFTs) have been prepared by pulsed laser deposition (PLD) for the first time here. With ultrathin amorphous ZnSnO ( ${a}$ -ZTO) films and the related UTFTs as a comparison, the properties of ultrathin a-IZO films and behaviors of the corresponding UTFTs were studied in detail. Also, we have taken a new approach to compare the content of oxygen vacancies ( ${V}_{\textit {O}}$ ) in amorphous oxide semiconductors (AOSs) of different systems, which explains their different properties and behaviors well. The thickness of the ultrathin a-IZO film is approximately 3.1 nm. Compared to ultrathin a-ZTO films, ultrathin a-IZO films depict lower ${V}_{O}$ content and lower carrier concentration. In addition, ultrathin ${a}$ -IZO films display very high transmittance over 95% in the visible region. Furthermore, a-IZO UTFTs exhibit better performance than a-ZTO UTFT, such as a lower off-current of 3.3 $\times \,\,10^{-10}$ A, a larger ${I} _{ \mathrm{\scriptscriptstyle ON}}/{I} _{ \mathrm{\scriptscriptstyle OFF}}$ ratio of $1.5\times 10^{7}$ , a larger $\mu _{\text {sat}}$ of 20.7 cm $^{2}\,\,{V} ^{-1}\,\,{s} ^{-1}$ , a smaller ${V} _{\text {th}}$ of 1.2 V (operating in the enhancement mode), a lower subthreshold swing (SS) of 0.303 V/decade, and a lower ${N} _{t}$ of $8.9\times 10^{11}$ cm−2. Meanwhile, the long-term stability of a-IZO UTFT is similar to a-ZTO UTFT. Above all, a-IZO UTFTs exhibit excellent performance and may be a promising candidate for future displays.

In this study, high temperature catalytic gasification of petroleum coke pyrolysis char is studied. The influence of variant catalysts with high melting point and catalysts addition amount are explored, simultaneously the catalytic mechanisms are explored in depth. The results show that the petroleum coke pyrolysis char has a high crystallinity of 65.5% and gasification process is divided into two stages at lower and higher temperature. All catalysts can significantly reduce the gasification temperature, especially the final temperature. NaAlO2 has the highest catalytic performance of improving gasification reactivity by ~1.68 times and reducing gasification final temperature by ~170 °C, while the catalytic effect of MgO, Fe2O3, CaO and Fe3O4 at lower temperature are not obvious. With NaAlO2 addition increasing, especially above 0.8%, the gasification reactivity of petroleum coke pyrolysis char is improved prominently. Different catalysts have variant catalytic mechanisms. The activation of NaAlO2 is relatively stable with temperature increasing and is proven to be an ideal catalyst for petroleum coke high temperature gasification.

We examine an amorphous oxide semiconductor (AOS) of ZnRhCuO. The a-ZnRhCuO films are deposited at room temperature, having a high amorphous quality with smooth surface, uniform thickness and evenly distributed elements, as well as a high visible transmittance above 87% with a wide bandgap of 3.12 eV. Using a-ZnRhCuO films as active layers, thin-film transistors (TFTs) and gas sensors are fabricated. The TFT behaviors demonstrate the p-type nature of a-ZnRhCuO channel, with an on-to-off current ratio of ∼ 1 × 103 and field-effect mobility of 0.079 cm2V–1s–1. The behaviors of gas sensors also prove that the a-ZnRhCuO films are of p-type conductivity. Our achievements relating to p-type a-ZnRhCuO films at room temperature with TFT devices may pave the way to practical applications of AOSs in transparent flexible electronics.

Ultra-thin amorphous ZnSnO (a-ZTO) films were deposited by pulsed laser deposition at room temperature and annealed at various temperatures for ultra-thin-film transistors (UTFTs). The thicknesses of the ultra-thin a-ZTO films are approximately 3.1 nm. The electrical resistivity of the nanofilms decreases greatly with the annealing temperature initially increasing. All the UTFTs with annealing temperature ranging from 250 to 450 °C exhibit good switching properties operating in the enhancement mode with the field-effect mobility of above 8.2 cm2 V−1 s−1. The annealing treatment exhibits extreme importance for the UTFTs to obtain better performance as oxygen vacancy is controlled easily in the ultra-thin films by annealing. The 350 °C-annealed a-ZTO UTFT depicts the largest field-effect mobility of 20.9 cm2 V−1 s−1, the minimum threshold voltage of 2.3 V, the minimum subthreshold swing of 0.339 V/decade, the minimum density of the interfacial trap states of 1.02 × 1012 cm−2 and a large on/off current ratio of 3.3 × 107. Besides, the UTFT with the annealing temperature of 450 °C depicts excellent long-term stability under bias stress due to the least oxygen vacancies. The observations will offer basic design guideline for improvement and future applications of UTFTs.

A design gauge pressure of an eco-friendly gas insulated switchgear (GIS) with an application of vacuum interrupters (VIs) ranges from 0.1 to 0.3MPa. Therefore, a high differential pressure is imposed on bellows of the VIs, which increases the fatigue failure risk of the bellows after cycles of operations. Although, there are some empirical equations recommended by the Chinese National Standard GB/T 12777-2008 which can be used to evaluate the fatigue life of the bellows, there still remains little understanding on the fatigue life of the bellows when the VI is subjected to a high differential pressure and a high operating velocity. The objective of this paper is to determine the relationship between the fatigue life of bellows and high differential pressure and high operating velocity. A fluid-structure interaction simulation is set up to analyze the equivalent stress and the fatigue life of VI bellows under differential gauge pressure ranging from 0.1MPa to 0.3MPa, and under differential operating velocity ranging from 2m/s to 4m/s. The simulation result shows that with an increasing of the pressure and operating velocity, the equivalent stress increases and the fatigue life decreases from 47957 cycles under 0.1MPa and 2m/s to 489 cycles under 0.3MPa and 4m/s. At last, a comparison between the simulation result and the empirical equations shows a limitation of the empirical equations, in which there is lacking of the operating velocity.

Ultrathin amorphous ZnSnO (a-ZTO) films and ultrathin amorphous ZnGeSnO (a-ZGTO) films with various Ge contents were deposited by pulsed laser deposition for ultra-thin-film transistors (UTFTs). The thicknesses of the channel layers are approximately 3.2 nm. The properties of these ultrathin films and behaviors of these UTFTs were comparatively studied in detail. The a-ZTO ultrathin film exhibited a low concentration of the oxygen vacancy (VO) compared to a-ZGTO ultrathin films. Among all the UTFTs, the a-ZTO UTFT demonstrated the undoubtedly best performance with an on/off current ratio of more than 107, the largest field-effect mobility of 23.2 cm2 V−1 s−1, a positive threshold voltage of 2.0 V, a very small subthreshold swing of 0.31 V/decade, and the best long-term stability under bias stress, suggesting that the introduction of VO suppressors is dispensable with such a small thickness. Above all, the concentration of the oxygen vacancy is easily controlled in the ultrathin a-ZTO nanofilms, leading to the UTFTs operating in the enhancement mode with a high field-effect mobility of 23.2 cm2 V−1 s−1 and excellent long-term stability. The a-ZTO ultrathin film and ultra-thin-film transistor are very potential for future electrical applications with their excellent properties.