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• InGaSnO thin film transistors (TFTs) with high mobility (>50 cm2/Vs) were prepared. • Gallium doping improves the electrical performance and stability of InGaSnO TFTs. • The thermal budget can be controled below 150 ℃ without other equipment and process. • Oxygen vacancy and interfacial defect density can be reduced by gallium doping. In this work, InGaSnO thin film transistors (TFTs) with high mobility (>50 cm2/Vs) were prepared by a simple co-sputtering process at a low temperature of 150 ℃. In the co-sputtering process of InSnO and Ga 2 O 3 , the composition of InGaSnO can be reasonably controlled by adjusting the sputtering power in the radio frequency plasma, which significantly affects the electrical performance and stability of InGaSnO TFTs. The highly overlapping 5 s electron cloud of In and Sn and the high binding energy of Sn-O lay the foundation for the high mobility of InGaSnO TFTs. The defects related to oxygen in the channel are suppressed by the reasonable control of the composition of Ga in the multicomponent oxides. Meanwhile, the interface defects between the gate dielectric and the active layer are reduced, and a dense metal-oxygen-metal network is formed which is conducive to electron transmission. We have achieved an InGaSnO TFTs with mobility of 58.7 cm2/Vs and threshold voltage of -1.33 V. The stability under positive and negative bias stress is also significantly improved. In general, a simple co-sputtering process is entirely feasible to realize high-mobility oxide TFTs. The control of the process temperature below 150 ℃ also extends its application in flexible electronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • TZO CNRs with controllable morphology and composition through a traditional metal assisted CVD technique were fabricated. • Three self-powered photodetectors were fabricated using TZO CNRs/Si heterojunction which could detect UV-NIR selectively. • IV-characteristics on illumination of UV and/or NIR radiation show good and fast response. Tellurium dioxide (TeO 2) doped zinc oxide (ZnO) composite nanorods (TZO CNRs) were first synthesized by chemical vapor deposition method on a p-type silicon substrate covered by a sputtered gold (Au) film. The morphologies, structures, compositions and optical properties of the TZO CNRs can be modulated with the TeO 2 content. Three typical self-powered TZO CNRs/Si heterojunction photodetectors named device 1, 2 and 3 according to the different TeO 2 contents and TZO CNR morphologies are designed. Device 1 based on 1.81 At% Te content TZO CNRs can detect UV lights with wavelength from 290 to 380 nm and showed a responsivity of 4.3 mA/W, a detectivity of 1.1 × 1012 cmHz1/2W−1 upon exposure to 370 nm light at a zero-bias voltage. Device 2 based on 5.86 At% Te content TZO CNRs is found to be selectively sensitive to UV and NIR lights. Device 3 based on 9.23 At% Te content TZO CNRs is found to be also selectively sensitive to NIR lights. Its most sensitive wavelength is 1040 nm with responsivity and detectivity of 24.6 mA/W and 4.12 × 1012 cmHz1/2W−1, respectively. In addition, the mechanism that led to their typical properties of these devices are also elucidated. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) based on ZnO were fabricated on a p -Si substrate by using a pulsed laser deposition system. Significant electroluminescence (EL) improvement was demonstrated with the insertion of an HfO 2 electron blocking layer (EBL) in n -ZnO/ p -Si heterojunctions. Distinct near-band-edge emission at around 392 nm accompanying by a broadly strong visible emission was achieved when a proper thickness of HfO 2 EBL was used. Current-voltage and capacitance-voltage measurements confirmed that a proper thickness of the HfO 2 EBL can effectively balance the injection of electrons and holes, resulting in an increase of radiative recombination in the ZnO active layer and thus enhancing the EL performance of the devices. Five independent emissions corresponding to five different transition processes were proposed to clarify the EL origination of the n -ZnO/HfO 2 / p -Si heterojunction LEDs by Gaussian deconvolutions. It is hoped that results in this work should be helpful for the development of ZnO-based LEDs that can integrate ZnO with the Si planar technology. [ABSTRACT FROM AUTHOR]

Three-dimensional hybrid structure with Ni 3 S 2 nanorod arrays as core material and NiCo hydroxide nanosheets as shell material is fabricated directly on flexible Ni foam. This hierarchical hybrid structure without any additives and binders behaves good electrochemical properties including a high specific capacitance of 1833.7 F g −1 (5.13 F cm −2 ) at a current density of 1 A g −1 , good rate capability with 88.27% capacitance retention at a current density of 20 A g −1 and great cyclic stability. Moreover, an asymmetric supercapacitor (ASC) based on NiCo hydroxide@Ni 3 S 2 hybrid structure on Ni foam as positive electrode and activated carbon as negative electrode is successfully assembled to further evaluate the electrochemical properties of the hybrid structure in a full-cell configuration. The ASC device also performs excellent electrochemical properties including a large potential window of 0–1.8 V, a high specific capacitance of 215.8 F g −1 at a current density of 1 A g −1 and long-term cycling performance. In the meantime, the ASC device also delivers a high energy density of 92.8 Wh kg −1 at a power density of 1.0 KW kg −1 . These results suggest that 3D NiCo hydroxide@Ni 3 S 2 hybrid structure has promising potential for use in high-performance supercapacitor. [ABSTRACT FROM AUTHOR]

TiO 2 nanoflowers composed of nano-needles had been synthesized by hydrothermal method and their field electron emission properties were studied for the first time, which exhibit a low turn-on field of 4.76 V/μm, a high field enhancement factor of up to 5216. This performance was better than that of the as reported TiO 2 nanostructure arrays. The efficient field emission behaviours were found to be not only attributed to their 3 dimensional structures of the nanoflowers but also related to their nano-needle morphology. Besides, self-powered ultraviolet photodetector based on TiO 2 nanoflowers had been fabricated and it showed an obvious response trend in both UV and visible regions with good repeatability and stability, also the photoresponse mechanism at zero bias had been depicted through the energy band theory. [ABSTRACT FROM AUTHOR]

Fiber supercapacitors have attracted public attentions because of their merits of relatively high capacitance density, flexibility and easy integration with various electronic devices. In this work, a flexible coaxial-type fiber solid-state asymmetrical supercapacitor (ASC) based on Ni 3 S 2 nanorod array electrode and pen ink electrode was successfully fabricated. The Ni 3 S 2 nanorod array electrode was synthesized by directly growing Ni 3 S 2 nanorod arrays on a nickel wire through a facile hydrothermal method and the pen ink electrode as negative electrode was synthesized by a simple dip-coating method. The solid-state ASC device presents a stable voltage window of 1.4 V and behaves a high specific capacitance of 34.9 F g −1 (87.25 F cm −1 ) at a scan rate of 10 mV s −1 . Compared with the symmetric supercapacitor (SSC) based on Ni 3 S 2 electrodes, the ASC device provide an increased energy density of 8.2 Wh kg −1 (0.81 mWh cm −3 ) at the power density of 214.6 W kg −1 (21.12 mW cm −3 ). In addition, the ASC device also exhibits excellent electrochemical stability with 93.1% of initial specific capacitance after 3000 consecutive cycles and good mechanical stability. These encouraging results present its great potential in flexible solid-state energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The InGaSnO thin film transistors after in-situ Ar plasma treatment enhanced the electrical performance and stability. • In-situ Ar plasma processing is simple, time-saving, and does not depend on other external equipment, reducing the thermal budget. • In-situ Ar plasma treatment reduces oxygen vacancy and interfacial defect density, reduces surface roughness, and improves film quality. High-performance InGaSnO thin film transistors are successfully fabricated with a reduced thermal budget by an in-situ Ar plasma treatment process. This process does not require external equipment for plasma treatment of the deposited film, which ensures the original vacuum environment and uses plasma energy for weak treatment. The atomic force microscope measurement shows that the surface roughness of the InGaSnO thin film decreased from 0.472 nm to 0.266 nm after treatment. The reduction of oxygen vacancy defect states is verified by the O 1s spectrum of X-ray photoelectron spectroscopy, and its interfacial defect density is also significantly reduced. The stabilities of InGaSnO TFTs are also considerably improved, with the threshold voltage shift under the negative bias stress test reduced to 0.39 V, better than annealing at 300 °C. Ar plasma treatment improves film quality and enhances device performance, which exhibits high field-effect mobility (30.8 cm2/Vs), a small sub-threshold swing (0.32 V/decade), and a low threshold voltage (−0.54 V). Overall, in-situ Ar plasma treatment not only reduces the thermal budget but also simplifies the process, enabling the utility of long-term high-temperature annealing, showing its potential in flexible display applications. [ABSTRACT FROM AUTHOR]

In this work, three dimensional Co 9 S 8 nanorod@Ni(OH) 2 nanosheet core-shell structure is directly fabricated on flexible carbon cloth by a simple low temperature hydrothermal method. This structure with good electrochemical performance could be applied for supercapacitor electrode material. Firstly, this three dimensional structure possesses high specific capacitance of 1620 F g −1 , which is 1.7 times of the specific capacitance of the pure Ni(OH) 2 electrode and 2.5 times of that of the pure Co 9 S 8 electrode. Secondly, this hybrid electrode exhibits a very high energy density of 70.0 Wh Kg −1 at the power density of 305.7 W kg −1 . In addition, the hybrid electrode displays good cycling stability with 104.5% of the initial capacitance after 2000 continuous cycles. Furthermore, the hybrid electrode with three dimensional structure possesses excellent flexibility and has almost the same cyclic voltammetry curve under different bending angles. Thus, the designed electrode holds great promises for light weight, flexible, high energy density supercapacitor applications. [ABSTRACT FROM AUTHOR]

In this article, we in situ fabricated copper sulfide (CuS) on fluorinated tin oxide (FTO) substrate using a low temperature and low cost hydrothermal method and then organic solar cells (OSCs) were fabricated by using a thin layer of CuS film as hole transporting layer (HTL). Our CuS films, consisting of two-dimensional (2D) intersected hexagonal nanosheets, are stoichiometric and show p-type electrical conductivity, a good transparency and a high hole mobility. The Fermi level, valence and conduction band energies for CuS HTL are characterized in detail through photoelectron spectroscopy studies. The small energy barrier between the valance band of CuS and the HOMO of poly(3-hexylthiophene) (P3HT) and the high hole mobility and electrical conductivity of CuS nanosheet film benefit for the hole transporting. Therefore, CuS HTL to OSCs results in a power conversion efficiency of 3.4% with P3HT and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as the active layer, which is a 13.3% increase in performance than devices with a poly (3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) HTL. Therefore, low-cost, environmental friendly and stable CuS is an appropriate choice for hole transporting materials (HTMs) in OSCs. [ABSTRACT FROM AUTHOR]

The electrical characteristics and reliability of Hf-In-Zn-O (HIZO) metal-oxide-semiconductor capacitors (MOSCAPs) with a microporous SiO2-based electric-double-layer (EDL) dielectric were investigated. Experimental results indicated that the HfO2 interlayer could effectively improve the interface quality, thus leading to reduced interface states, suppressed hysteresis and decreased gate leakage current. Improved performance was achieved for the HIZO MOSCAPs with HfO2/EDL stack gate dielectrics (HECAPs), such as a large capacitance density of 0.7μF/cm2, an interface state density of 5.7×1011 eV−1/cm2, a fixed charge density of 1.9×1012 cm−2, a hysteresis voltage of 230mV and a gate leakage current density of 3×10−6 A/cm2 at +1V. Moreover, enhanced reliability of the HECAPs was obtained with an elevated dielectric breakdown voltage of 4.8V and a small increase (< 15 %) of gate leakage after gate bias stressing at 2V for 3600s. [ABSTRACT FROM AUTHOR]

Background: Since the outbreak of a new emerging virulent pseudorabies virus mutant in Chinese pig herds, intensive research has been focused on the construction of novel gene deletion vaccine based on the variant virulent viruses. An ideal vaccine candidate is expected to have a balanced safety and immunogenicity. Results: From the infectious clone of PRV AH02LA strain, a TK deletion mutant was generated through two-step Red mutagenesis. After homologous recombination with a transfer vector, a TK&gE dual deficient mutant PRV (PRVΔTK&gE-AH02) was generated, and its structure verified by PCR, RFLP and sequencing. Growth kinetics test showed that PRVΔTK&gE-AH02 reached a titer of 107.5 TCID50 /mL on ST cells. The PRVΔTK&gE-AH02 at a dose of 106.0 TCID50 /animal was not virulent in mice or 1-day-old piglets with maternal PRV antibodies. No clinical signs or virus shedding were detected in 28~ 35-day-old piglets without maternal PRV antibodies after nasal or intramuscular administration with a dose of 106.0 TCID50, although it caused one death of four 1-day-old piglets without maternal PRV antibodies. In the efficiency test of PRVΔTK&gE-AH02, all four 28~ 35-day-old piglets without PRV antibody in the challenge control showed typical clinical symptoms and virus shedding, and two died at 4~ 5 days post challenge. All piglets in 105.0, 104.0 and 103.0 TCID50/dose PRVΔTK&gE-AH02 groups provided complete protection against challenge at only 7 days post intramuscular vaccination. More importantly, PRVΔTK&gE-AH02 stopped virus shedding in these piglets. In contrast, all four piglets in PRV Bartha K61 vaccine group developed high body temperature (≥40.5 °C) and viral shedding, despite they had mild or even no clinical symptoms. Conclusions: The constructed TK&gE dual deletion mutant PRVΔTK&gE-AH02 can reach high titers on ST cells. The live vaccine of PRVΔTK&gE-AH02 is highly safe, and can not only provide clinical protection but also stops virus shedding. This study suggests that PRVΔTK&gE-AH02 might work as a promising vaccine candidate to combat the PRV variant emerging in Chinese herds since 2011. [ABSTRACT FROM AUTHOR]