Bias-dependent photoresponse of T-WTegrown by chemical vapor deposition.

The type-II Weyl semimetal T-WTeis one of the wonder materials for high-performance optoelectronic devices. We report the self-powered T-WTephotodetectors and their bias-dependent photoresponse in the visible region (405, 520, 638 nm) driven by the bulk photovoltaic effect. The device shows the responsivity of 15.

Phase transition in WSeTe monolayers driven by charge injection and pressure: a first-principles study.

Alloying strategies permit new probes for governing structural stability and semiconductor-semimetal phase transition of transition metal dichalcogenides (TMDs). However, the possible structure and phase transition mechanism of the alloy TMDs, and the effect of an external field, have been still unclear. Here, the enrichment of the Te content in WSeTe monolayers allows for coherent structural transition from the H phase to the T' phase.

Correction: Silver/silver halide supported on mesoporous ceria particles and photo-CWPO degradation under visible light for organic compounds in acrylonitrile wastewater.

[This corrects the article DOI: 10.1039/D1RA04465F.].

A polar-switchable and controllable negative phototransistor for information encryption.

Anomalous negative phototransistors have emerged as a distinct research area, characterized by a decrease in channel current under light illumination. Recently, their potential applications have been expanded beyond photodetection. Despite the considerable attention given to negative phototransistors, negative photoconductance (NPC) in particular remains relatively unexplored, with limited research advancements as compared to well-established positive phototransistors.

Optically Induced Multistage Phase Transition in Coherent Phonon-Dominated -GeTe.

Ultrafast photoexcitation can decouple the multilevel nonequilibrium dynamics of electron-lattice interactions, providing an ideal probe for dissecting photoinduced phase transition in solids. Here, real-time time-dependent density functional theory simulations combined with occupation-constrained DFT methods are employed to explore the nonadiabatic paths of optically excited -GeTe. Results show that the short-wavelength ultrafast laser is capable of generating full-domain carrier excitation and repopulation, whereas the long-wavelength ultrafast laser favors the excitation of lone pair electrons in the antibonded state.

Directly measuring flexoelectric coefficients of the van der Waals materials.

Flexoelectricity originates from the electromechanical coupling interaction between strain gradient and polarization, broadly applied in developing electromechanical and energy devices. However, the study of quantifying the longitudinal flexoelectric coefficient () which is important for the application of atomic-scale two-dimensional (2D) materials is still in a slow-moving stage, owing to the technical challenges. Based on the free-standing suspension structure, this paper proposes a widely applicable method and a mensurable formula for determining the constant of layer-dependent 2D materials with high precision.

Tunable lattice dynamics and dielectric functions of two-dimensional BiOSe: striking layer and temperature dependent effects.

Two-dimensional (2D) BiOSe semiconductors with a narrow band gap and ultrahigh mobility have been regarded as an emerging candidate for optoelectronic devices, whereas the ambiguous phonon characteristics and optical properties still limit their future applications. Herein, high-quality centimeter-scale 2D BiOSe films are successfully synthesized to disclose the lattice dynamics and dielectric functions under the control of thickness and temperature. It has been demonstrated that the stronger electrostatic Bi-Se interactions result in a stiffened phonon vibration of thicker BiOSe layers.

Ultrathin Fe-ReS Nanosheets as Electrocatalysts for Accelerating Sulfur Reduction in Li-S Batteries.

Lithium-sulfur batteries are promising next-generation energy storage systems with high theoretical specific capacity. Despite extensive research efforts, it is still challenging to rationally design electrocatalysts with fast kinetics and effective adsorption of polysulfides. Herein, Fe-doped ReS (Fe-ReS) ultrathin nanosheets are prepared as an electrocatalyst to trap the intermediates and accelerate the sulfur reduction reaction kinetics.

Ultra-Stable, Endurable, and Flexible SbTeSe Phase Change Devices for Memory Application and Wearable Electronics.

Flexible memory and wearable electronics represent an emerging technology, thanks to their reliability, compatibility, and superior performance. Here, an SbTeSe (STSe) phase change material was grown on flexible mica, which not only exhibited superior nature in thermal stability for phase change memory application but also revealed novel function performance in wearable electronics, thanks to its excellent mechanical reliability and endurance. The thermal stability of SbTe was improved obviously with the crystallization temperature elevated 60 K after Se doping, for the enhanced charge localization and stronger bonding energy, which was validated by the Vienna simulation package calculations.

Silver/silver halide supported on mesoporous ceria particles and photo-CWPO degradation under visible light for organic compounds in acrylonitrile wastewater.

Silver/silver halide supported on ordered mesoporous ceria particles (Ag/AgCl/CeO) were rapidly prepared by microwave-assisted soft template method, deposition precipitation method and photoreduction method, using cerium nitrate and silver nitrate as raw materials and block copolymer F127 as a template. The morphology, structure and chemical composition of the catalyst were characterized by XRD, SEM, EDS, TEM, N adsorption-desorption and UV-Vis Drs. Catalytic wet peroxide system assisted with visible light photocatalysis (photo-CWPO) was conducted to investigate the performance of organics degradation by Ag/AgCl/CeO as a catalyst in acrylonitrile wastewater.

Designing Monoclinic Heterophase Coexistence for the Enhanced Piezoelectric Performance in Ternary Lead-Based Relaxor Ferroelectrics.

Enhanced piezoelectric, dielectric properties and thermal stability in ternary relaxor-PbTiO based ferroelectric crystals are expected to develop the next-generation of electromechanical devices. However, due to their increased disorder compared to other ferroelectrics, designing a controllable phase boundary structure and engineered domain remains a challenging task. Here, we construct a monoclinic heterophase coexisting in a ternary Pb(InNb)O-Pb(MgNb)O-PbTiO single crystal with optimized composition and an ultrahigh piezoelectric coefficient of 1400 pC N, to quantify the correlation between spontaneous nanopolarity and phase heterogeneity, in an attempt to understand the origin of the exceptional functionalities.

Ultrabroadband Tellurium Photoelectric Detector from Visible to Millimeter Wave.

Ultrabroadband photodetection is of great significance in numerous cutting-edge technologies including imaging, communications, and medicine. However, since photon detectors are selective in wavelength and thermal detectors are slow in response, developing high performance and ultrabroadband photodetectors is extremely difficult. Herein, one demonstrates an ultrabroadband photoelectric detector covering visible, infrared, terahertz, and millimeter wave simultaneously based on single metal-Te-metal structure.

Flexo-photoelectronic effect in n-type/p-type two-dimensional semiconductors and a deriving light-stimulated artificial synapse.

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.

Thermal Conductivity of Large-Area Polycrystalline MoSe Films Grown by Chemical Vapor Deposition.

It is of great importance to understand the thermal properties of MoSe films for electronic and optoelectronic applications. In this work, large-area polycrystalline MoSe 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 MoSe film.

Optically Modulated HfS-Based Synapses for Artificial Vision Systems.

The simulation of human brain neurons by synaptic devices could be an effective strategy to break through the notorious "von Neumann Bottleneck" and "Memory Wall". Herein, opto-electronic synapses based on layered hafnium disulfide (HfS) transistors have been investigated. The basic functions of biological synapses are realized and optimized by modifying pulsed light conditions.

Ferroelectric-Modulated MoS Field-Effect Transistors as Multilevel Nonvolatile Memory.

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 nonvolatile memory. In FeFETs, the conductivity states of the semiconductor are utilized to explore the polarization directions of the ferroelectric material. Herein, we report FeFETs based on a few layers of MoS on a 0.

P-N conversion of charge carrier types and high photoresponsive performance of composition modulated ternary alloy W(SSe) field-effect transistors.

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.

Roles for heterodimerization of APJ and B2R in promoting cell proliferation via ERK1/2-eNOS signaling pathway.

Apelin receptor (APJ) and bradykinin B2 receptor (B2R) play an important role in many physiological processes and share multiple similar characteristics in distribution and functions in the cardiovascular system. We first identified the endogenous expression of APJ and B2R in human umbilical vein endothelial cells (HUVECs) and their co-localization on human embryonic kidney (HEK) 293 cells membrane. A suite of bioluminescence and fluorescence resonance energy transfer (BRET and FRET), proximity ligation assay (PLA), and co-immunoprecipitation (Co-IP) was exploited to demonstrate formation of functional APJ and B2R heterodimer in HUVECs and transfected cells.

Superior and Reversible Lithium Storage of SnO/Graphene Composites by Silicon Doping and Carbon Sealing.

The poor cycle stability and reversibility seriously hinder the widespread application of SnO materials as anodes for lithium-ion batteries (LIBs). A novel sandwich-architecture composite of Si-doped SnO nanorods and reduced graphene oxide with carbon sealing (Si-SnO@G@C) is engineered and fabricated by a facile two-step hydrothermal process and subsequent annealing treatment, which exhibit not only extraordinary rate performance and ultrahigh reversible capacity but also excellent cycle stability and high electrical conductivity as the anode of LIBs. The Si-doped SnO nanoparticles on the surface of graphene were firmly wrapped in the C-coating and formed a porous sandwich structure, which can efficiently prevent the Sn nanoparticles from aggregation and provide more extra space for accommodating the volume variations and more active sites for reactions.

Mixed-Dimensional Van der Waals Heterostructure Photodetector.

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/VO mixed-dimensional vdW heterostructure is discovered.

Ferroelectric and dipole control of band alignment in the two dimensional InTe/InSe heterostructure.

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/InSe. It is found that band alignment is closely dependent on the ferroelectric polarization of InSe.

Large-Scale Growth and Field-Effect Transistors Electrical Engineering of Atomic-Layer SnS.

2D layers of metal dichalcogenides are of considerable interest for high-performance electronic devices for their unique electronic properties and atomically thin geometry. 2D SnS 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.

Probing Effective Out-of-Plane Piezoelectricity in van der Waals Layered Materials Induced by Flexoelectricity.

Many van der Waals layered 2D materials, such as h-BN, transition metal dichalcogenides (TMDs), and group-III monochalcogenides, have been predicted to possess piezoelectric and mechanically flexible natures, which greatly motivates potential applications in piezotronic devices and nanogenerators. However, only intrinsic in-plane piezoelectricity exists in these 2D materials and the piezoelectric effect is confined in odd-layers of TMDs. The present work is intent on combining the free-standing design and piezoresponse force microscopy techniques to obtain and directly quantify the effective out-of-plane electromechanical coupling induced by strain gradient on atomically thin MoS and InSe flakes.

InN superconducting phase transition.

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.