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The transparent conductive CuCr1–xNixO2 (0 ≤ x ≤ 8%) films were prepared by sol–gel method with two-step annealing process. The structure, morphology, phonon modes, chemical composition, optical ba...

It is of great importance to understand the thermal properties of MoSe2 films for electronic and optoelectronic applications. In this work, large-area polycrystalline MoSe2 films are prepared using a low-cost, controllable, large-scale, and repeatable chemical vapor deposition method, which facilitates direct device fabrication. Raman spectra and X-ray diffraction patterns indicate a hexagonal (2H) crystal structure of the MoSe2 film. Ellipsometric spectra analysis indicates that the optical band gap of the MoSe2 film is estimated to be ∼1.23 eV. From the analysis of the temperature-dependent and laser-power-dependent Raman spectra, the thermal conductivity of the suspended MoSe2 films is found to be ∼28.48 W/(m·K) at room temperature. The results can provide useful guidance for an effective thermal management of large-area polycrystalline MoSe2-based electronic and optoelectronic devices.

Unipolar barrier structures are used to suppress dark current in photodetectors by blocking majority carriers. Designing unipolar barriers with conventional materials is challenging due to the strict requirements of lattice and band matching. Two-dimensional materials have self-passivated surfaces and tunable band structures, and can thus be used to design unipolar barriers in which lattice mismatch and interface defects are avoided. Here, we show that band-engineered van der Waals heterostructures can be used to build visible and mid-wavelength infrared unipolar barrier photodetectors. Our nBn unipolar barrier photodetectors, which are based on a tungsten disulfide/hexagonal boron nitride/palladium diselenide heterostructure, exhibit a low dark current of 15 pA, a photocurrent of 20 μA and a detectivity of 2.7 × 1012 cm Hz1/2 W−1. Our pBp unipolar barrier photodetectors, which are based on a black phosphorus/molybdenum disulfide/graphene heterostructure, exhibit a room-temperature detectivity of 2.3 × 1010 cm Hz1/2 W−1 in the mid-wavelength infrared region under blackbody radiation. The pBp devices also show a dichroic ratio of 4.9 under blackbody radiation, and a response time of 23 μs under 2 μm laser illumination. Band-engineered van der Waals heterostructures that block dark current without suppressing photocurrent can be used to build detectors with high room-temperature detectivity for visible light and blackbody infrared light.

Semiconductor-based heterogeneous photocatalysis has received much attention. A plasma-assisted method for synthesizing CuO was developed and used to decorate ZnO nanorods. High quality monoclinic ...

Ultrathin Al2O3 insulating intercalations with different thicknesses and numbers, prepared by atomic layer deposition technology, were introduced into Ba(Zr0.2Ti0.8)O3 (BZT) relaxor ferroelectric films as the dielectric for electrostatic energy storage capacitors. The phase structure, microstructure and electrical properties were investigated in detail. Due to the insertion of insulating layers, the films show less leakage current and enhanced voltage endurance capability when the thickness of single Al2O3 intercalation exceeds a threshold (0.45–0.9 nm). The voltage endurance capability can be more enhanced by increasing the number of Al2O3 intercalations. For energy storage applications, the energy storage density and efficiency obtained from the polarization-electric field loops are significantly improved owing to the suppressed leakage and enhanced voltage endurance ability. The results promote the application of BZT-based films in electrostatic energy storage. It is demonstrated that the introduction of atomic-layer-deposited insulating intercalations with controllable thickness, such as those fabricated by ALD method, is an effective way to improve the electrical performance of devices based on composite materials.

In general, self-powered photodetectors are tedious and costly. Here, high-performance self-powered visible photodetectors based on MAPbI3 films were fabricated by using asymmetric Au electrodes. For this construction of photodetector, the illumination passing through the translucent MAPbI3 film can reduce the Schottky barrier between the lower electrode and perovskite, and the Au particles doping into the MAPbI3 at the contact areas between the upper electrode and films can also change the Schottky barrier, which leads to the formation of built-in potential. Without an applied bias, the photodetectors exhibit an ultralow dark current of $\sim 3$ pA. At the power intensity of 2.92 mW/cm2 under 635 nm illumination, a decent responsivity of 10 mAW−1, a high specific detectivity of $3.3 \times 10^{11}$ cmHz1/2W−1, and an external quantum efficiency of 2.1% are obtained. The on/off ratio reaches 104 and the response speed is less than 50 ms. Our results pave a new design concept to form a self-powered perovskite-based photodetector.

Summary Perovskite solar cells (PSCs) suffer from significant nonradiative recombination, limiting their power conversion efficiencies. Here, for the first time, we directly observe a complete transformation of perovskite MAPbI3 surface region energetics from p- to n-type during defect passivation caused by natural additive capsaicin, attributed to the spontaneous formation of a p-n homojunction in perovskite active layer. We demonstrate that the p-n homojunction locates at ∼100 nm below perovskite surface. The energetics transformation and defect passivation promote charge transport in bulk perovskite layer and at perovskite/PCBM interface, suppressing both defect-assisted recombination and interface carrier recombination. As a result, an efficiency of 21.88% and a fill factor of 83.81% with excellent device stability are achieved, both values are the highest records for polycrystalline MAPbI3 based p-i-n PSCs reported to date. The proposed new concept of synergetic defect passivation and energetic modification via additive provides a huge potential for further improvement of PSC performance.

Flexoelectricity and photoelectricity with their coupled effect (the so-called flexo-photoelectronic effect), are of increasing interest in the study of electronics and optoelectronics in van der Waals layered semiconductors. However, the related device design is severely restricted owing to the ambiguous underlying physical nature of flexo-photoelectronic effects originating from the co-manipulation of light and strain-gradients. Here, flexoelectric polarization and the flexo-photoelectronic effect of few-layered semiconductors have been multi-dimensionally investigated from high-resolution microscopic characterization on the nanoscale, physics analysis, and deriving a device design. We found that two back-to-back built-in electric fields form in bent InSe and WSe2, and greatly modulate the transport behaviors of photogenerated carriers, further facilitating the separation of photogenerated electron–hole pairs and trapping the holes/electrons in InSe or WSe2 channels, recorded in realtime by a home-made technique of lighting Kelvin probe force microscopy (KPFM). The slow release of trapped carriers contributes to the photoconductance relaxation after illumination. Utilizing the photoconductance relaxation, a light-stimulated artificial synapse based on the flexo-photoelectronic effect of bent InSe has been achieved. Significantly, all the pair-pulse facilitation (PPF) behavior, spike frequency-dependent excitatory post-synaptic current (EPSC) and the transition from short-term memory (STM) to long-term memory (LTM) have been successfully realized in this artificial synapse. This work adds to the investigation of flexo-photoelectronic effects on 2D optoelectronics, and moves towards the development of 2D neuromorphic electronics.

Ferroelectric field-effect transistors (FeFETs) with semiconductors as the channel material and ferroelectrics as the gate insulator are attractive and/or promising devices for application in nonvo...

Background: Imbalanced immune response and hepatic fibrosis are key factors related to the progression of chronic liver diseases. Tetramethylpyrazine (TMP), a natural alkaloid, has been widely used for treating liver injury. In this study, we explored the effect of TMP on hepatic fibrosis and the related mechanisms regulating autophagy. Methods: A rat model of hepatic fibrosis and a model using an hepatic stellate cell line (HSC-T6) were created using CCl4 and platelet-derived growth factor (PDGF). Staining with haematoxylin and eosin (HE), Masson’s stain, and TUNEL were performed for pathological diagnosis. ELISA, Western blotting, and immunofluorescence analyses were conducted to determine the expression levels of the specific markers for fibrosis, autophagy, inflammation, and signalling pathways. Results: TMP treatment significantly rescued pathological injury and hepatic fibrosis. It also alleviated imbalances in the immune system, accumulation of extracellular matrix, and autophagy signals in hepatic fibrosis. At the same time, we found that application of the autophagy inducer rapamycin enhanced the therapeutic effect of TMP, whereas the autophagy inhibitor 3-methyladenine, PI3K pathway inhibitor LY294002, and AKT pathway agonist SC79 did the opposite. Conclusions: TMP exerts therapeutic effects in hepatic fibrosis mainly through promoting autophagy to ameliorate inflammation by inhibiting the AKT–mTOR signalling pathway, providing a new perspective for the treatment of chronic liver diseases.

The purpose of this study was to explore the role of prophylactic antiviral therapy in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients with negative HBV-DNA. The study included 79 HBV-related HCC patients with preoperative negative HBV-DNA who underwent hepatectomy. Patients were prospectively assigned to two groups: preoperative antiviral treatment group (n = 39) and untreated group (n = 40). Follow-up visits were performed with patients regularly once per month. The data for the two groups were analyzed including HBV activation; tumor recurrence; liver function; 1-, 2-, and 3-year survival rate; and cumulative survival time. In the antiviral group, 1 of 39 (2.56%) patients had HBV activation, while there were 8 of 40 (20%) with HBV activation in the untreated group (p

Sandwich-structured CdS/Au/ZnO nanorods were prepared by embedding Au nanoparticles in CdS coating-covered ZnO nanorods for high photochemical and photoelectrochemical activities via semiconductor ...

ZnO has attracted considerable attention as an ultraviolet (UV) light emitting material. Many efforts have been made to promote efficiency for UV emission. We report large enhancement in UV emission from ZnO nanorod (NR) arrays by covering with Ti coatings. Together with morphology and structure characterization, the capability of UV emission from the Ti-coating-covered ZnO (Ti/ZnO) NR arrays was evaluated by systematically examining the photoluminescence at room and low temperatures. At room temperature, the bare ZnO NR arrays are capable of emitting a photoluminescence composed of a strong UV near-band-edge (NBE) emission of ZnO and a weak visible emission associated with deep-level defects in ZnO. The UV NBE emission is enhanced by about 24 times after covering the ZnO NR arrays with Ti coatings. The UV NBE emission increases drastically as the temperature drops, with the increase of the UV NBE emission of the Ti-covered ZnO NR arrays being much faster than that of the bare ZnO NR arrays. The UV NBE em...

The impact of environmental regulation on enterprise innovation is closely related to the competitiveness of the enterprise and sustainable development of the regional economy, but existing research does not provide a consistent view. This paper summarizes the impacts of environmental regulation on enterprise innovation from the perspectives of technological innovation, product innovation, system innovation and ecological innovation. We find that the impacts of environmental regulation on enterprise innovation behaviour are complex, and that the impacts can be reflected together by the four aspects above and even by their interaction. Moreover, the impacts are not limited to the creation of new technologies, products, and systems but also include their adoption and application. In particular, whether the Porter hypothesis is true and which versions of the Porter hypothesis environmental regulation causes in enterprise innovation depend on enterprise characteristics, means of environmental regulation, and enterprises' strategic behaviours in an enterprise ecosystem. Finally, we propose five potential research directions: quantifying the degree of enterprise innovation caused by environmental regulation, the impacts of environmental regulation on sustainable economic development from an enterprise ecosystem perspective, the impacts of enterprise innovation on environmental regulation, the role of enterprise initiative in the relationship between environmental regulation and enterprise innovation, and social security issues and the integration of eliminated enterprises resulting from environmental regulation.

Transition metal dichalcogenides (TMDs) have emerged as a new class of two-dimensional (2D) materials, which are promising for diverse applications in nanoelectronics, optoelectronics, and photonics. To satisfy the requirements of the building blocks of functional devices, systematic modulation of the band gap and carrier type of TMDs materials becomes a significant challenge. Here, we report a salt-assisted chemical vapor deposition (CVD) approach for the simultaneous growth of alloy W(SxSe1−x)2 nanosheets with variable alloy compositions. Electrical transport studies based on the as-fabricated W(SxSe1−x)2 nanosheet field-effect transistors (FETs) demonstrate that charge carrier types of alloy nanosheet transistors can be systematically tuned by adjusting the alloy composition. Temperature-dependent current measurement shows that the main scattering mechanism is the charged impurity scattering. The effective Schottky barrier heights of bipolar W(SxSe1−x)2 transistors are initially increased and then decreased with increasing positive (or negative) gate voltage, which is tunable by varying the alloy composition. In addition, the tunability of these W(SxSe1−x)2-based ambipolar transistors is suitable for logic and analog applications and represents a critical step toward future fundamental studies as well as for the rational design of new 2D electronics with tailored spectral responses, and simpler and higher integration densities. Finally, the high photoresponsivity (up to 914 mA W−1) and detectivity (4.57 × 1010 Jones) of ultrathin W(SxSe1−x)2 phototransistors imply their potential applications in flexible light-detection and light-harvesting devices. These band gap engineered 2D structures could open up an exciting opportunity and contribute to finding diverse applications in future functional electronic/optoelectronic devices.

α-In2Se3, a recently reported two-dimensional (2D) van der Waals (vdW) ferroelectric, is gaining significant attention due to its potential applications in nano-scale devices. Here, we have systematically investigated the electronic properties of three configurations of In2Se3/MoS2(I, II, III) heterostructures by first-principles calculations. The results reveal that the intrinsic ferroelectricity polarization in α-In2Se3 can dramatically tune the electronic properties. When the out-of-plane ferroelectric polarization field is pointing from In2Se3 towards MoS2, the energy band of the heterostructure is type-II band alignment with a band gap of 0.8 eV, which is beneficial for carrier separation. With reversal of the ferroelectric polarization, the band alignment switches from type-II to type-I with a band gap of 1.6 eV, which is suitable for luminescence device applications. Based on the nonequilibrium Green's function method (NEGF), the calculated photoinduced current density under visible-light radiation is up to ∼0.5 mA cm−2 in the In2Se3/MoS2(I) heterostructure, which can remarkably exceed that of thin-film silicon devices at a phonon energy below 2.5 eV. Moreover, the band alignment transition can also be realized through the application of an external electric field. We believe that the present work will greatly enlarge the potential applications of the In2Se3-based heterostructures in future nano-optoelectronic devices.

Constructing two dimensional (2D) van der Waals (vdW) heterostructures and understanding their electronic properties are pivotal for developing novel electronic devices. In this work, by using the first-principles calculations, we theoretically demonstrate that the 2D GaSe/GeS van der Waals (vdW) heterobilayer is a robust type-II band alignment semiconductor with a direct band gap of 1.8 eV. It exhibits a remarkable absorbance coefficient of ∼105 cm−1 from the UV to visible light region and a high carrier mobility with anisotropic character. The photoelectric conversion efficiency (PCE) shows a tremendous enhancement under external strain, and shows an efficiency of up to ∼16.8% at 2% compressive strain. Besides, we find that applying an external electric field can effectively modulate its band gap and band offset. Interestingly, a larger external electric field can induce nearly free electron (NFE) states around the conduction band minimum (CBM) in the GaSe/GeS heterobilayer, which leads to the band transition from a semiconductor to metallic status. These results indicate that 2D GaSe/GeS heterostructures will have widespread application prospects in future photovoltaic and optoelectric nanodevices.

Inorganic CsPbBr3 perovskite solar cell (PSC) has attracted much attention owing to its outstanding air and thermal stability and low cost manufacture process. Crystalline TiO2 (c-TiO2) has been widely used as electron-transporting layer (ETL) material for inorganic CsPbBr3 PSC. However, c-TiO2 requires high-temperature (>450 °C) fabrication process which impedes the application of flexible inorganic CsPbBr3 PSC and its low electron mobility further limits the performance enhancement. Herein, we prepared novel amorphous Nb2O5 (a-Nb2O5) ETL through a facile room-temperature sputtering method for inorganic planar CsPbBr3 PSC. The PSC with a-Nb2O5 ETL has gained a champion efficiency of 5.74%, which is higher than that of the PSC (5.12% or 4.67%) based on crystalline Nb2O5 (c-Nb2O5) ETL or c-TiO2 ETL by high-temperature (500 °C) annealing. The improved photovoltaic characteristic for CsPbBr3 PSC with a-Nb2O5 ETL may be ascribed to its suitable work function, high optical transmittance, low charge recombination at the a-Nb2O5/CsPbBr3 interface and the superior crystallinity of CsPbBr3 film deposited on a-Nb2O5 ETL. Moreover, the a-Nb2O5-based CsPbBr3 PSC without encapsulation exhibits a good long-term stability in ambient atmosphere. This work offers a new research direction for preparing high-performance inorganic PSC.

Recently, researchers have focused on optoelectronics based on two-dimensional van der Waals materials to realize multifunctional memory and neuron applications. Layered indium selenide (InSe) semiconductors satisfy various requirements as photosensitive channel materials, and enable the realization of intriguing optoelectronic applications. Herein, we demonstrate InSe photonic devices with different trends of output currents rooted in the carrier capture/release events under various gate voltages. Furthermore, we reported an increasing/flattening/decreasing synaptic weight change index (∆Wn) via a modulated gate electric field, which we use to imitate medicine-acting metaplasticity with effective/stable/ineffective features analogous to the synaptic weight change in the nervous system of the human brain. Finally, we take advantage of the low-frequency noise (LFN) measurements and the energy-band explanation to verify the rationality of carrier capture-assisted optoelectronics applied to neural simulation at the device level. Utilizing optoelectronics to simulate essential biomedical neurobehaviors, we experimentally demonstrate the feasibility and meaningfulness of combining electronic engineering with biomedical neurology.

Low-dimensional Te-based photodetectors exhibit blackbody response and achieve record-set performance metrics., Blackbody-sensitive room-temperature infrared detection is a notable development direction for future low-dimensional infrared photodetectors. However, because of the limitations of responsivity and spectral response range for low-dimensional narrow bandgap semiconductors, few low-dimensional infrared photodetectors exhibit blackbody sensitivity. Here, highly crystalline tellurium (Te) nanowires and two-dimensional nanosheets were synthesized by using chemical vapor deposition. The low-dimensional Te shows high hole mobility and broadband detection. The blackbody-sensitive infrared detection of Te devices was demonstrated. A high responsivity of 6650 A W−1 (at 1550-nm laser) and the blackbody responsivity of 5.19 A W−1 were achieved. High-resolution imaging based on Te photodetectors was successfully obtained. All the results suggest that the chemical vapor deposition–grown low-dimensional Te is one of the competitive candidates for sensitive focal-plane-array infrared photodetectors at room temperature.

P-type CuO films were prepared by solution processed method and annealed at 300 °C with the annealing time of 10, 30, 60, 90, and 120 min, respectively. X-ray diffraction and atomic force microscopy results reveal that the CuO film microstructures, crystallinity and grain size can be modified by annealing time. The CuO film annealed at 30 min exhibits the optimal crystalline quality. The annealing time shows a significant impact on the mobility, Ion/Ioff ratio and subthreshold swing (SS) values of the prepared CuO thin-film transistors (TFTs). By changing the annealing time, the mobility increases from 1.6 × 10−4 to 1.2 × 10−2 cm2 V−1 s−1 while the Ion/Ioff ratio increases from 2 × 103 to 2 × 104. Moreover, the transistor with annealing time of 30 min achieves the optimal field-effect mobility (1.2 × 10−2 cm2 V−1 s−1), Ion/Ioff ratio (2 × 104), and SS value (6.3 Vdec−1). It can be ascribed to fewer grain boundaries and better interface contact of the CuO film, which will reduce the densities of trapping centers and scattering centers. This work demonstrates that the crystalline quality and microstructures of CuO film and TFTs performance can be modulated by annealing time.

Searching for novel two-dimensional (2D) materials with tunable electrical and optical properties is significant to develop next-generation multifunctional nanoscale optoelectronic devices. The new insulated Mg(OH)2 is a promising and stable 2D material to construct heterojunction with transition metal dichalcogenides (TMDs). Here, WS2-Mg(OH)2 is experimentally designed and investigated. The similarity of lattice constants for the two materials is confirmed with selected area electron diffraction for the first time. By stacking Mg(OH)2 layers on WS2 monolayer, the Fermi level of WS2 is distinctly elevated, making the WS2-Mg(OH)2 a promising heterostructure for constructing and optimizing tunable electronic devices. We also showed the adjustable transition properties with enhanced coupling effect by thinning the Mg(OH)2 layers in the heterostructure. This study not only demonstrates the tunable Fermi levels and optical characteristics of WS2-Mg(OH)2, but also could promote the broad investigations of novel 2D materials for various optoelectronic device applications in nanoscale.

Sb2Se3 thin films prepared by vapor transport deposition (VTD) method have been treated by post annealing process at 200 °C in vacuum condition for 1 h, and the comparative studies between the post annealing treatment (PAT) and without the treatment were carried out. The device efficiency was improved from 4.89% to 5.72% by PAT via the augment of open-circuit voltage and fill factor. Electrical properties from dark J-V and C-V measurements, structural properties from X-ray diffraction, Raman and scanning electron microscope measurements, defect properties from admittance measurements have been compared for the two cell samples. The Sb2Se3 cell sample with PAT was found to own less parallel current pathways, larger built-in voltage, better crystalline and lower defects densities, which may account for the efficiency enhancement.

Enhancing the ultraviolet emission from ZnO nanostructures is of interest in the applications for fabricating ZnO-based short-wavelength light-emitting devices. We decorated the surfaces of hydrothermally grown ZnO nanorods with WS2 by pulsed laser deposition and succeeded in enhancing the ultraviolet emission of ZnO. The WS2-decorated ZnO nanorods were characterized for morphology, structure and optical properties. Bare ZnO nanorods have a high capability of emitting ultraviolet excitonic emission. WS2 decorating resulted in the tailoring of the ultraviolet emission and an enhancement over 2 times was obtained for the ZnO nanorods covered with a thin WS2 coating. At low temperatures, more enhancement in the ultraviolet emission of ZnO can be achieved due to WS2 decorating.

Neuromorphic electronics with two-dimensional van der Waals materials meet the ever-increasing demands of both the semiconductor industry and biological engineering, such as miniaturization, structure flexibility, multifunctionality, and low power consumption. However, the majority of reported electronic devices achieve multifarious memory storage states or synaptic plasticity through regulation of an electrical or an optical signal. Herein, we propose an innovative touch-modulated device based on an indium selenide/hexagonal boron nitride/graphene van der Waals heterostructure coupled with a triboelectric nanogenerator. The device is prepared utilizing a simple copper grid shadow mask instead of the expensive and cumbersome electron beam lithography process, exhibits high mobility of 829 cm2 V−1 s−1, low voltage, and low power consumption. Nonvolatile memory with self-writing power, durability and multibit data storage is achieved through mechanical modulation without an additional gate-voltage supply. Moreover, by adjusting the distance between the two friction layers, essential synaptic plasticity, including short-term and long-term potentiation/depression and paired-pulse facilitation/depression, are successfully imitated in the device. Most importantly, we achieve ultralow power consumption of 165 aJ in tribotronic synapses owing to the ultra-high mobility of InSe. Our tribotronic synapse with self-writing power has great potential to simulate the low-power-consuming neuromorphic bioelectronic devices with multiple functions and lays the foundation for future advanced neuromorphic systems and artificial intelligence.

Understanding how the temperature affects the structural and electronic properties for two-dimensional (2D) semiconductors could promote the application and development of the nanoelectronic devices. Here, temperature dependence of lattice structure for indium selenide (InSe) nanosheet and the corresponding electronic properties of 3-nm-indium-deposited InSe field-effect transistor (FET) are systematically demonstrated. Analyses of Raman spectra suggest that the difference of phonon frequency ($\Delta\omega$) for A$_{1g}^{2}$ mode is found to be 3.14 cm$^{-1}$, which is larger than that of the E$_{2g}^{1}$ mode due to the stronger electron-phonon coupling for A$_{1g}^{2}$ mode. The device performance based on indium-deposited InSe is systematically explained by the Kelvin probe force microscopy (KPFM) and the predicted energy band structure. Furthermore, FETs based on temperature and the thickness variable InSe flakes as the applicable devices are designed. Our findings are fundamental importance to explain the underlying physics in intrinsic InSe transistor and improve further applications.

Van der Waals (vdW) heterostructures, integrated two-dimensional (2D) materials with various functional materials, provide a distinctive platform for next-generation optoelectronics with unique flexibility and high performance. However, exploring the vdW heterostructures combined with strongly correlated electronic materials is hitherto rare. Herein, a novel temperature-sensitive photodetector based on the GaSe/VO2 mixed-dimensional vdW heterostructure is discovered. Compared with previous devices, our photodetector exhibits excellent enhanced performance, with an external quantum efficiency of up to 109.6% and the highest responsivity (358.1 mA·W-1) under a 405 nm laser. Interestingly, we show that the heterostructure overcomes the limitation of a single material under the interaction between VO2 and GaSe, where the photoresponse is highly sensitive to temperature and can be further vanished at the critical value. The metal-insulator transition of VO2, which controls the peculiar band-structure evolution across the heterointerface, is demonstrated to manipulate the photoresponse variation. This study enables us to elucidate the method of manipulating 2D materials by strongly correlated electronic materials, paving the way for developing high-performance and special optoelectronic applications.

Photodetectors based on p-type metal oxides are still a challenge for optoelectronic device applications. Many effects have been paid to improve their performance and expand their detection range. Here, high-quality Cu1-xNixO (x = 0, 0.2, and 0.4) film photodetectors were prepared by a solution process. The crystal quality, morphology, and grain size of Cu1-xNixO films can be modulated by Ni doping. Among the photodetectors, the Cu0.8Ni0.2O photodetector shows the maximum photocurrent value (6 × 10-7 A) under a 635 nm laser illumination. High responsivity (26.46 A/W) and external quantum efficiency (5176%) are also achieved for the Cu0.8Ni0.2O photodetector. This is because the Cu0.8Ni0.2O photosensitive layer exhibits high photoconductivity, low surface states, and high crystallization after 20% Ni doping. Compared to the other photodetectors, the Cu0.8Ni0.2O photodetector exhibits the optimal response in the near-infrared region, owing to the high absorption coefficient. These findings provide a route to fabricate high-performance and wide-detection range p-type metal oxide photodetectors.

Hepatic ischemia/reperfusion injury (IRI) is a result of the ischemic cascade and may occur in the settings of liver trauma, resection and transplantation. Components of the complement system have been indicated to be mediators of hepatic IRI and regulators of liver regeneration. As such, their potential to mediate both beneficial and harmful effects render them key targets for therapy. In the present study, the mechanisms of complement mediating hepatic IRI were discussed with a focus on the different functions of complement in hepatic injury and liver recovery, and an explanation for this apparent paradox is provided, i.e. that the complement products C3a and C5a have an important role in liver damage; however, C3a and C5a are also necessary for liver regeneration. Furthermore, situated at the end of the complement activation cascade, the membrane attack complex is crucial in hepatic IRI and inhibiting the complex with a site-targeted murine complement inhibitor, complement receptor 2-CD59, may improve liver regeneration after partial hepatectomy, even when hepatectomy is combined with ischemia and reperfusion.

Metal sulfide has the potential to take the place of high temperature sintered TiO2 as electron transportation layer for perovskite solar cell (PSC) with improved light stability and suppressed hysteresis. In this work, CdS films were used as independent or buffered electron transport layer for planar perovskite solar cell by a low-temperature RF sputtering method for the first time. The effects of surface roughness and optical absorption of CdS films on the photovoltaic performance of PSCs were discussed. The PSC with sputtered CdS film shows a higher open-circuit voltage (Voc) and efficiency of 13.17% than high temperature sintered TiO2 ETL (12.71%). Moreover, a RF sputtered CdS buffer layer between TiO2 and perovskite could tune the conduction band edge of TiO2 and perovskite and passivating the surface defects. Time resolved photoluminescence results indicate the RF sputtered CdS film buffer layer could accelerate charge transportation and a higher conversion efficiency over 16% has thus been achieved, with enhanced air stability and minimized hysteresis. These findings offer new research directions for low-temperature sputtered metal sulfide film as a promising electron transport material for stable and high efficient planar perovskite solar cell.

The optical properties of aluminum-doped zinc oxide (AZO) thin films were calculated rapidly and accurately by point-by-point analysis from spectroscopic ellipsometry (SE) data. It was demonstrated that there were two different physical mechanisms, i.e., the interfacial effect and crystallinity, for the thickness-dependent permittivity in the visible and infrared regions. In addition, there was a blue shift for the effective plasma frequency of AZO when the thickness increased, and the effective plasma frequency did not exist for AZO ultrathin films (

Phase change materials (PCMs) combined with silicon photonics are emerging as a promising platform to realize miniature photonic devices. We study the basic optical properties of a sub-wavelength-dimension silicon ridge waveguide with a 20-nm-thick Ge2Sb2Te5 (GST) top-clad layer. Numerical simulations show that the effective index of the Si-GST hybrid waveguide varies significantly when the GST changes from the amorphous to the crystalline states. This change can be utilized to make micron-size photonic devices. To experimentally verify the effectiveness of the Si-GST hybrid waveguide on light wave manipulation, we fabricated a series of unbalanced Mach-Zehnder interferometers with one arm connected with a section of Si-GST hybrid waveguide in different lengths. The transmission spectra are measured and the complex effective indices are extracted for GST at crystalline, amorphous and intermediate phases. The experimental results overall agree well with the simulation ones. The nonvolatile property of GST makes it attractive to reduce the static power consumption. This research represents a significant step towards the realization of ultra-compact Si-GST hybrid devices that will play a key role in high-density photonic integrated circuits, opening the door to many potential applications, including optical switch, memory and logic operation.

Highly optically transparent and electrically conductive Al-doped ZnO (AZO) thin films with varied Al concentrations were synthesized by means of reactive deposition of ZnO host films and in-situ doping of Al by pulsed laser co-ablation of a Zn target and an Al target with the assistance of an oxygen plasma. The optical and electrical properties of AZO films were tailored by the adjustment of Al concentration which was realized by varying the laser fluence on the Al target. The morphology, composition and structure as well as the optical and electrical properties were characterized and the effects of Al doping and post-deposition annealing were investigated. Similar with undoped ZnO, the synthesized AZO films have a hexagonal wurtzite structure with the crystallinity deteriorated, present high visible transparency with the absorption edge blue shifted and show good electrical properties with the electrical conductivity increased. The structural, optical and electrical properties are strongly dependent on Al concentration and are significantly improved after annealing in H2/N2 mixed gas. Annealed AZO films containing 3.0 at% Al have optical properties including an absorption edge near 325 nm and an optical band gap of 3.67 eV and electrical properties covering an electrical resistivity of 5.27 × 10−4 Ω cm and a carrier concentration of 1.11 × 1021 cm−3 with a Hall mobility of 10.7 cm2/V s.

Two-dimensional (2D) crystalline carbonitride C3N, as a very attractive material, has received extensive attention. By using the first-principles calculations, we systematically studied the electronic properties of antimonene/C3N van der Waals (vdW) heterojunction. The results show that the heterostructure has an inherent type-II band alignment with an indirect band gap. Moreover, the band gap of the C3N/antimonene heterojunction can be adjusted linearly within a certain range by applying vertical strain and electric field. The calculated absorption curve shows that the antimonene/C3N heterostructure can exhibit good visible-light absorption performance, and the optical properties of the C3N/antimonene heterojunction can be changed by applying biaxial and vertical strain, which can be expected to have potential applications in photovoltaic devices.

The mechanism of open voltage (Voc) deficit in all-inorganic CsPbBr3 planar solar cell has been systematically investigated by depositing the TiO2 electron transport layer with magnetron sputtering (MS) and spin-coating (SC) deposition, respectively. It was found that SC-TiO2 film reveals higher optical band gap (3.67 eV) than MS-TiO2 film (3.62 eV). However, CsPbBr3 planar solar cell based on MS-TiO2 exhibits less Voc deficit and higher photoelectric conversion efficiency (5.48%). The mechanism behind performance enhancement of MS-TiO2-based device is suitable Fermi level of MS-TiO2 and high electronic transport capacity with low charge recombination at CsPbBr3/MS-TiO2 interface. Moreover, the unencapsulated all-inorganic planar devices show a superior stability when stored in air at room temperature for two months. This work provides a novel approach to improve the performance of all-inorganic perovskite solar cell.

Active and widely controllable phase transition optical materials have got rapid applications in energy-efficient electronic devices, field of meta-devices and so on. Here, we report the optical properties of the vanadium dioxide (VO2)/aluminum-doped zinc oxide (Al:ZnO) hybrid n-n type heterojunctions and the corresponding electro-optic performances of the devices. Various structures are fabricated to compare the discrepancy of the optical and electrical characteristics. It was found that the reflectance spectra presents the wheel phenomenon rather than increases monotonically with temperature at near-infrared region range. The strong interference effects was found in the hybrid multilayer heterojunction. In addition, the phase transition temperature decreases with increasing the number of the Al:ZnO layer, which can be ascribed to the electron injection to the VO2 film from the Al:ZnO interface. Affected by the double layer Al:ZnO, the abnormal Raman vibration mode was presented in the insulator region. By adding the external voltage on the Al2O3/Al:ZnO/VO2/Al:ZnO, Al2O3/Al:ZnO/VO2 and Al2O3/VO2/Al:ZnO thin-film devices, the infrared optical spectra of the devices can be real-time manipulated by an external voltage. The main effect of joule heating and assistant effect of electric field are illustrated in this work. It is believed that the results will add a more thorough understanding in the application of the VO2/transparent conductive film device.

Background Yes-associated protein (YAP) overexpression is reported to be associated with risk of hepatocellular carcinoma (HCC) but current studies have not explored the relationship between YAP expression with HCC clinicopathological features. Methods To assess these associations, a meta-analysis was performed which included four eligible studies including 391 HCC cases and 334 controls. There were eight eligible studies to investigate the association between YAP expression in HCC and clinicopathological features of liver cancer patients. Literature was obtained from PubMed, Embase, Wangfang and China National Knowledge Infrastructure. Results Analysis indicated that YAP expression in HCC was greater than in adjacent non-tumour tissue (odds ratio [OR], 15.80, 95% confidence interval [CI], 10.53-23.70, P

InN superconductivity is very special among III–V semiconductors, as other III–V semiconductors (such as GaAs, GaN, InP, InAs, etc.) usually lack strong covalent bonding and thus seldom show superconductivity at low temperatures. Here, we probe the different superconducting phase transitions in InN highlighted by its microstructure. Those chemical-unstable phase-separated inclusions, such as metallic indium or In2O3, are intentionally removed by HCl acid etching. The quasi-two-dimensional vortex liquid-glass transition is observed in the sample with a large InN grain size. In contrast, the superconducting properties of InN with a small grain size are sensitive to acid etching, showing a transition into a nonzero resistance state when the temperature approaches zero. Since the value of ξ0 (the zero-temperature-limit superconducting coherence length) is close to the grain size, it is suggested that individual InN grains and intergrain coupling should be responsible for the sample-dependent InN superconducting phase transition. Our work establishes a guideline for engineering superconductivity in III-nitride.

Br-rich inorganic perovskite CsPbIBr2, has gained intense attention for photovoltaic application owing to its excellent thermal stability and appropriate band gap for the top cell of tandem solar cell. However, in most case, the open voltage (Voc) of highly efficient CsPbIBr2 solar cell is below 1.3 V which is far from the requirement for a top cell. Herein, a novel multi-source cation/anion co-doping strategy has been used in CsPbIBr2 solar cell, which produces multiple benefits to improve the device performance. Using a multi-source co-doping strategy, carbon-based planar CsPbIBr2 solar cell achieved a respectable Voc of 1.37 V with an efficiency of 10.78%, which is the highest Voc reported for highly efficient CsPbIBr2 solar cell so far. This simple multi-source cation/anion doping strategy not only improves the film quality but also strengthens built-in potential, resulting in the significant enhancement of Voc. Moreover, device with multi-source co-doping shows a much better long-term stability than that of undoped device. This work opens up a facile and efficient method to improve the Voc and efficiency of inorganic perovskite solar cell for tandem solar cell and other optoelectronic application.

The optical bandgap manipulation engineering of two-dimensional (2D) semiconductor heterostructure plays an important role in the development of optoelectronics and nanoelectronics. In this work, the photoluminescence (PL) peak of the MoS2/TaSe2 heterostructure is slightly red-shifted compared with that of MoS2. The result is explained by the electron transfer from TaSe2 to MoS2, which is theoretically calculated to be about 0.00405 e. Furthermore, the experimental and theoretical results show that the work function of the heterostructure is less than that of the MoS2. The present study promises for exploring the potential tunable optical bandgap optoelectronic devices.

δ opioid receptor (DOR) was the first opioid receptor of the G protein‑coupled receptor family to be cloned. Our previous studies demonstrated that DOR is involved in regulating the development and progression of human hepatocellular carcinoma (HCC), and is involved in the regulation of the processes of invasion and metastasis of HCC cells. However, whether DOR is involved in the development and progression of drug resistance in HCC has not been reported and requires further elucidation. The aim of the present study was to investigate the expression levels of DOR in the drug‑resistant HCC BEL‑7402/5‑fluorouracil (BEL/FU) cell line, and its effects on drug resistance, in order to preliminarily elucidate the effects of DOR in HCC drug resistance. The results of the present study demonstrated that DOR was expressed at high levels in the BEL/FU cells, and the expression levels were higher, compared with those in normal liver cells. When the expression of DOR was silenced, the proliferation of the drug‑resistant HCC cells were unaffected. However, when the cells were co‑treated with a therapeutic dose of 5‑FU, the proliferation rate of the BEL/FU cells was significantly inhibited, a large number of cells underwent apoptosis, cell cycle progression was arrested and changes in the expression levels of drug‑resistant proteins were observed. Overall, the expression of DOR was upregulated in the drug‑resistant HCC cells, and its functional status was closely associated with drug resistance in HCC. Therefore, DOR may become a recognized target molecule with important roles in the clinical treatment of drug‑resistant HCC.

Low-symmetry 2D materials with unique anisotropic optical and optoelectronic characteristics have attracted a lot of interest in fundamental research and manufacturing of novel optoelectronic devices. Exploring new and low-symmetry narrow-bandgap 2D materials will be rewarding for the development of nanoelectronics and nano-optoelectronics. Herein, sulfide niobium (NbS3 ), a novel transition metal trichalcogenide semiconductor with low-symmetry structure, is introduced into a narrowband 2D material with strong anisotropic physical properties both experimentally and theoretically. The indirect bandgap of NbS3 with highly anisotropic band structures slowly decreases from 0.42 eV (monolayer) to 0.26 eV (bulk). Moreover, NbS3 Schottky photodetectors have excellent photoelectric performance, which enables fast photoresponse (11.6 µs), low specific noise current (4.6 × 10-25 A2 Hz-1 ), photoelectrical dichroic ratio (1.84) and high-quality reflective polarization imaging (637 nm and 830 nm). A room-temperature specific detectivity exceeding 107 Jones can be obtained at the wavelength of 3 µm. These excellent unique characteristics will make low-symmetry narrow-bandgap 2D materials become highly competitive candidates for future anisotropic optical investigations and mid-infrared optoelectronic applications.

Two-dimensional (2D) materials with unique structural and physical properties are urgent to exploit and may be applied in the next-generation electronics and infrared detectors. The homojunction devices are ideal and promising candidates compared to heterojunction devices since there are no interface problems, such as unintentionally induced impurities and charge-trapped sites. In this work, we reported a high-performance MoSe2 homojunction infrared photodetector. MoSe2 homojunction devices directly consist of thick and thin MoSe2. MoSe2 homojunction diodes exhibit different rectified characteristics including forward and reverse rectifications, which are dependent on the back-gate voltage. Remarkably, MoSe2 homojunction photodetectors possess a broadband photoresponse with the wavelength from visible to near-infrared at room temperature. The responsivity of MoSe2 homojunction photodetectors under 940 nm laser illumination is approximately 2.25 A W−1. Additionally, the obtained specific detectivity of MoSe2 homojunction device is over 1010 Jones. Our findings provide an excellent way to fabricate feasible homojunction devices. Meanwhile, homojunction devices also show the wealthy potential in novel electronic and optoelectronic devices.

Two dimensional (2D) ferroelectric materials are gaining growing attention due to their nontrival ferroelectricity, and the 2D ferroelectric heterostructures with tunable electronic, optoelectronic, or even magnetic properties, show many novel properties that do not exist in their constituents. In this work, by using the first-principles calculations, we investigate the ferroelectric and dipole control of electronic structures of the 2D ferroelectric heterostructure InTe/In2Se3. It is found that band alignment is closely dependent on the ferroelectric polarization of In2Se3. By switching the polarization of In2Se3, the band alignment of InTe/In2Se3 switches from a staggered (type II) to a straddling type (type I), and the band gap changes from indirect gap 0.76 eV to direct gap 0.15 eV. When the ferroelectric field of In2Se3 is reversed, the band alignment of InTe/In2Se3 switches from type-I to type-II, and the band gap changes from indirect gap 0.76 eV to direct gap 0.15 eV. In addition, we find that the interlayer dipole can also effectively modulate the band structure and induce the type-I to type-II band alignment transition. Our present results indicate that the 2D ferroelectric heterostructure with the tunable band alignment and band gap can be of great significance in the optoelectronic devices.

2D layers of metal dichalcogenides are of considerable interest for high-performance electronic devices for their unique electronic properties and atomically thin geometry. 2D SnS2 nanosheets with a bandgap of ≈2.6 eV have been attracting intensive attention as one potential candidate for modern electrocatalysis, electronic, and/or optoelectronic fields. However, the controllable growth of large-size and high-quality SnS2 atomic layers still remains a challenge. Herein, a salt-assisted chemical vapor deposition method is provided to synthesize atomic-layer SnS2 with a large crystal size up to 410 µm and good uniformity. Particularly, the as-fabricated SnS2 nanosheet-based field-effect transistors (FETs) show high mobility (2.58 cm2 V-1 s-1 ) and high on/off ratio (≈108 ), which is superior to other reported SnS2 -based FETs. Additionally, the effects of temperature on the electrical properties are systematically investigated. It is shown that the scattering mechanism transforms from charged impurities scattering to electron-phonon scattering with the temperature. Moreover, SnS2 can serve as an ideal material for energy storage and catalyst support. The high performance together with controllable growth of SnS2 endow it with great potential for future applications in electrocatalysis, electronics, and optoelectronics.

The complement system is a key component of the body's immune system. When abnormally activated, this system can induce inflammation and damage to normal tissues and participate in the development and progression of a variety of diseases. In the past, many scholars believed that alcoholic liver disease (ALD) is induced by the stress of ethanol on liver cells, including oxidative stress and dysfunction of mitochondria and protease bodies, causing hepatocyte injury and apoptosis. Recent studies have shown that complement activation is also involved in the genesis and development of ALD. This review focuses on the roles of complement activation in ALD and of therapeutic intervention in complement-activation pathways. We intend to provide new ideas on the diagnosis and treatment of ALD.

The interface between III-V and metal-oxide-semiconductor materials plays a central role in the operation of high-speed electronic devices, such as transistors and light-emitting diodes. The high-speed property gives the light-emitting diodes a high response speed and low dark current, and they are widely used in communications, infrared remote sensing, optical detection, and other fields. The rational design of high-performance devices requires a detailed understanding of the electronic structure at this interface; however, this understanding remains a challenge, given the complex nature of surface interactions and the dynamic relationship between the morphology evolution and electronic structures. Herein, in situ transmission electron microscopy is used to probe and manipulate the structural and electrical properties of ZrO2 films on Al2 O3 and InGaAs substrate at the atomic scale. Interfacial defects resulting from the spillover of the oxygen-atom conduction-band wavefunctions are resolved. This study unearths the fundamental defect-driven interfacial electric structure of III-V semiconductor materials and paves the way to future high-speed and high-reliability devices.

Al doped ZnO (ZnO:Al) and Al–N co-doped ZnO (ZnO:Al–N) films were synthesized based on plasma assisted reactive deposition of ZnO matrix and in-situ doping of Al or co-doping of Al and N. Similar with undoped ZnO, the synthesized ZnO:Al and ZnO:Al–N films are hexagonal wurtzite in structure and exhibit high optical transparency in a wide spectral region. Al doping and Al–N co-doping in ZnO result in a significant variation of the optical properties in the ultraviolet (UV) region and an UV extension of the transparent range. Compared with undoped ZnO, the doped films show blue-shifted absorption edge of 320 nm and widened band gap of 3.69 eV after annealing in H2/N2 mixed gas because of the incorporation of dopants and the improvement in the crystal structure. The ZnO:Al film exhibits declined transparency in the near infrared (IR) region, while the ZnO film co-doped with Al and N preserves high transparency from near UV to medium IR in addition to the UV extension of the transparent range. The annealed ZnO:Al and ZnO:Al–N films show better electrical properties than those of the undoped ZnO film and the as-deposited doped ZnO films.