Search

The art integration of the Textile Colour Science curriculum means that the practical teaching of the course cannot be limited to scientific and technical experiments, but should be integrated with artistic colour matching and colour expression. The aim of the course should both include strengthen the students' understanding and consolidation of the basic theoretical knowledge of colour composition and the enhancement of the students' aesthetic awareness and artistic creation ability. Only through properly arrange the practical teaching section and impove the teaching method of the course, can the teaching objective be achieved.

Electronic and magnetic properties of the RB6 (R = La, Ce, Nd, Sm and Eu) crystals were investigated by using the first - principles method within the framework of the density functional theory. The ground state of lanthanum hexaboride (LaB6) is nonmagnetic crystal, while the others RB6 (R = Ce, Nd, Sm and Eu) are ferromagnetic crystal due to the partial occupations of electrons on 4f orbital for rare – earth atoms. We have done the prediction of lattice parameters, magneticmoments of magnetic ions and total magnetizations of the RB6 crystals.PACS numbers: 71.20.Eh, 75.50.-y

Over the past decades, construction of nanoscale electronic devices with novel functionalities based on low-dimensional structures, such as single molecules and two-dimensional (2D) materials, has been rapidly developed. To investigate their intrinsic properties for versatile functionalities of nanoscale electronic devices, it is crucial to precisely control the structures and understand the physical properties of low-dimensional structures at the single atomic level. In this review, we provide a comprehensive overview of the construction of nanoelectronic devices based on single molecules and 2D materials and the investigation of their physical properties. For single molecules, we focus on the construction of single-molecule devices, such as molecular motors and molecular switches, by precisely controlling their self-assembled structures on metal substrates and charge transport properties. For 2D materials, we emphasize their spin-related electrical transport properties for spintronic device applications and the role that interfaces among 2D semiconductors, contact electrodes, and dielectric substrates play in the electrical performance of electronic, optoelectronic, and memory devices. Finally, we discuss the future research direction in this field, where we can expect a scientific breakthrough.

Binary nanocrystalline rare-earth hexaboride is regarded as one of the promising optical absorption materials that possess the high transparency for visible light and the strong absorption for NIR due to the effects of localized surface plasmon resonance. In present work, we experimentally investigated the structural and optical absorption of ternary nanocrystalline Eu-doped SmB6 powder. As a result, it is found that the reaction temperature as an important factor not only refines the grain size, but also improves the powder dispersion of synthesized samples. The optical absorption results reveal that the transmittance wavelength of nanocrystalline SmB6 increases from 696 nm to exceeding 1000 nm with the Eu doping content increasing to x = 0.8. Theoretically, in order to study the transmittance wavelength tunable mechanisms of nanocrystalline Eu-doped SmB6, the electronic structure, density of states and energy loss function were calculated by first-principle calculation. It shows that the Eu2+ doping into SmB6 effectively reduces the plasma frequency excitation energy from 1.48 to 1.25 eV and leads to the transmittance wavelength redshift toward a higher wavelength. Based on above meaningful studies, present work is helpful for extension of optical applications of nanocrystalline SmB6 powder.

Purpose This paper aims to provide a flexible polyurethane (PU) film with visible light trapping ability, photothermal conversion and energy storage performance by covalently bonded a visible light absorbing dye into the polymer through copolymerization. Design/methodology/approach For this target solution copolymerization of diphenyl-methane-diisocyanate (MDI), poly(1,4-butylene adipate) (PBA2000), polyethylene glycol (PEG) of different molecular weight, self-made dye, 1,4-butanediol (BuOH) was carried out in a flame-dried flask under an inert nitrogen (N2) atmosphere. First, an isocyanate-terminated prepolymer of dried PEG, MDI and PBA2000 was prepared in dimethylformamide and stirred for 1 h at 35°C. Then, self-made dye and 1, 4-butanediol (BuOH) were added and heated at 85°C for 3 h to get photothermal conversion polyurethane (PTPU) solution. Allowed the solution to dry at room temperature for seven days and then at 65°C for 12 h to get PTPU films. Findings The flexible PU films with photothermal conversion and energy storage performances were successfully synthesized and the functional films presented both excellent energy storage and mechanical property when the molecular weight of PEG was in the range of 6,000∼10,000. Research limitations/implications The materials that were used in this research paper had a reasonably low cost. Also, the procedures for the synthesis of dye and polymers were extremely easy because there was no need for high pressure or temperature and no dangerous solvents were used. Practical implications The photothermal conversion property and mechanical performance of the synthesized flexible PU films were characterized. The results have proved that these films were soft and elastic, and have certain photothermal conversion and energy storage ability, thus can be used in the surface finishing of special fabric and leather. Originality/value Visible light trapping photothermal conversion PU flexible film with energy storage capability was prepared for the first time.

Due to the epistemic uncertainties involved in the numerical values of its parameters and its modeling, the system may not accomplish its function as required. Functional failure becomes an important factors in the natural circulation system operation failure, which needs to be considered in the system reliability analysis. In order to solve the problem of multi-dimensional uncertainty parameters and small functional failure probability of passive systems, an efficient functional reliability estimation method based on improved response surface and importance sampling subset simulation was presented. This method was applied in natural circulation cooling in XAPR reactor core. Combined with MLOCA, the uncertainties related to the input parameters and the model were considered. And then the probability of functional failure and the sensitivity measures were estimated with the combination of response surface method and importance sampling subset simulation method. The assessment results show that the functional failure probability is 3.796 × 10−3, and it is fully considered the functional failure in the passive system reliability analysis. Meanwhile, this method has high computed efficiency and excellent computed accuracy compared with traditional probability analysis methods, and it is robust to nonlinear functional function of XAPR.

Development of memory devices with ultimate performance has played a key role in innovation of modern electronics. As a mainstream technology nonvolatile memory devices have manifested high capacity and mechanical reliability, however current major bottlenecks include low extinction ratio and slow operational speed. Although substantial effort has been employed to improve their performance, a typical hundreds of micro- or even milli- second write time remains a few orders of magnitude longer than their volatile counterparts. We have demonstrated nonvolatile, floating-gate memory devices based on van der Waals heterostructures with atomically sharp interfaces between different functional elements, and achieved ultrahigh-speed programming/erasing operations verging on an ultimate theoretical limit of nanoseconds with extinction ratio up to 10^10. This extraordinary performance has allowed new device capabilities such as multi-bit storage, thus opening up unforeseen applications in the realm of modern nanoelectronics and offering future fabrication guidelines for device scale-up., Comment: Preprint version, to be published in Nature Nanotechnology (Submitted on August 16th, 2020)

2D functional materials, such as 2D magnet and superconductor, spark massive interests from synthesis, manipulation to application. Especially, FeTex with multi-phases provides an ideal platform to explore the possible superconducting, ferromagnetic or antiferromagnetic properties and even their functional heterostructures. Herein, we report a facile chemical vapor deposition (CVD) approach to synthesize ultrathin tetragonal FeTe (down to monolayer), hexagonal FeTe (down to 2.3 nm), and Fe-rich hexagonal FeTe with superlattice by tuning the growth temperature according to the phase diagram. Scanning transmission electron microscopy (STEM) is further performed to confirm the difference among these various FeTe phases. Magneto-transport illustrates that the tetragonal device displays a high linear magnetoresistance (LMR) up to 10.5% at 1.9 K, and the LMR of hexagonal FeTe reaches 5.8% at 1.9 K. Interestingly, O doped tetragonal thick FeTe displays a superconducting transition at 9 K, which can persist even at 16 T. In summary, this study illustrates a phase-selective synthesis of FeTex ultrathin crystals, providing promising opportunities to construct complicated devices such as ferromagnet/antiferromagnet, magnet/superconductor heterostructures.

Wrinkles are special surface corrugations in two-dimensional materials, which can be used to tune their electronic, optical, and chemical properties. There have been many studies focusing on the wr...

Two-dimensional (2D) materials are considered to be promising candidates for constructing revolutionary electronic devices. However, difficulties in controlling the polarity, concentration, and spatial distribution of charge carriers in 2D materials make the construction of 2D p–n junctions rather challenging. Here, we report the successful construction of ultrafast-programmable 2D p–n homojunctions with a semi-floating-gate configuration based on a vertically stacked molybdenum disulfide (MoS2)/hexagonal boron nitride/multilayer graphene van der Waals heterostructure. By partially electrostatically doping the MoS2 channel under different control-gate voltage pulses, three types of 2D homojunctions, including p–n, n+–n, and n–n, can be constructed. The 2D p–n homojunction can be programmed at an ultrafast speed of within 160 ns and exhibits a large rectification ratio of ∼104. Based on a modified Shockley equation, an ideality factor of ∼2.05 is extracted, indicating that the recombination process dominated the transport mechanism. The MoS2 2D p–n homojunction shows a maximum electrical power conversion efficiency of up to 2.66% under a weak light power of 0.61 nW and a high photovoltage responsivity of 5.72 × 109 V W−1. These results indicate that the ultrafast-programmable 2D p–n homojunction has great potential for use in high-performance photovoltaics and optoelectronics.

In order to investigate the effect of differences in amino acid alkyl chains, In order to investigate the effect of difference amino acid alkyl chains on the Rare earth complexes, the lipoaminic acids rare earth surfactant complexes of yttrium hexanoyl alaninc acid (Y(hex-ala)3), yttrium octanoyl alaninc (Y(oct-ala)3) and yttrium dodecanoyl alaninc acid (Y(dod-ala)3) are synthesized by the reaction of C9H17NO3, C11H21NO3, C15H29NO3 with YCl3, respectively. These complexes have been compared to the yttrium octanoate soap (Y(octnt)3). At the same time, the formation of molecular glasses of these complexes are compared with the aggregation behavior in solution, evaluate properties as glass. Furthermore, the aggregation behavior of the above surfactant complexes in the pure solvent are studied using nuclear magnetic resonance (NMR) spectrometry, vapor pressure osmometry (VPO), electrical conductivity and Fourier Transform-Infrared spectroscopy (FT-IR). As results, these Y(III) complexes aggregate in the organic solvents system and tend to form aggregates. After the organic solvents evaporated, organic rare earth vitreous bodies was obtained.

Graphene on SiO2 enables fabrication of Si-technology-compatible devices, but a transfer of these devices from other substrates and direct growth have severe limitations due to a relatively small grain size or device-contamination. Here, we show an efficient, transfer-free way to integrate centimeter-scale, single-crystal graphene, of a quality suitable for electronic devices, on an insulating SiO2 film. Starting with single-crystal graphene grown epitaxially on Ru(0001), a SiO2 film is grown under the graphene by stepwise intercalation of silicon and oxygen. Thin (∼1 nm) crystalline or thicker (∼2 nm) amorphous SiO2 has been produced. The insulating nature of the thick amorphous SiO2 is verified by transport measurements. The device-quality of the corresponding graphene was confirmed by the observation of Shubnikov-de Haas oscillations, an integer quantum Hall effect, and a weak antilocalization effect within in situ fabricated Hall bar devices. This work provides a reliable platform for applications of large-scale, high-quality graphene in electronics.

As multifunctional materials, rare-earth hexaborides (RB6) display many interesting physical properties such as optical absorption, magnetic and thermionic emission. With the wide application of rare earth hexaboride and the continuous extension of its research fields, researchers have studied the synthesis of multi-rare earth hexaboride nano-powders and their thermal emission and light absorption properties. In the present work, ternary Single-phase LaxPr1−xB6 submicron powders are successfully synthesized using a solid-state reaction, in which lanthanum chloride (LaCl3) and praseodymium chloride (PrCl3) are used as rare-earth source and NaBH4 as the boron source under continuous vacuum conditions. The reaction temperature is 1150 °C and the holding time is 2 h. The Pr doping effects on crystal structure, grain morphology, and optical absorption properties were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and ultraviolet-vis absorption measurements. The XRD patterns show that the diffraction peaks are sharp and well-defined, and no other extra impurity peaks were detected, indicating the characteristics of well-crystallized materials. It is found that all the LaxPr1−xB6 solid powders are of single phase. The SEM results demonstrate that the cubicshaped ternary LaxPr1−xB6 submicron crystals with a size of 50~200 nm are obtained. The TEM images reveal the cubic single-crystalline nature, and the FFT patterns implies the lattice fringe d = 0.416 nm which agrees well with the (100) crystal plane. The elements mapping results indicates that the Pr atoms occupied the lattice sites of LaB6. The optical absorption results show that the absorption valley of LaB6 are located at 591 nm. With the increase of Pr doping contents from 0.2 to 0.8, the absorption valley moves from 596.3 nm to 612.9 nm, indicating the characteristics of visible light high transparency. The first-principle calculation results manifest that the move of the absorption valley of LaB6 in the visible region after doping Pr is related to the decrease of kinetic energy of electrons near the Fermi plane. X-ray photoelectron spectroscopy (XPS) analysis shows that the La and Pr exist in the type of La3+ and Pr3+ in LaxPr1−xB6. Therefore, it exists as an efficient optical absorption material. The LaxPr1−xB6 should open up a new route to extend the optical applications of rare-earth hexaborides.

Atomically thin solid-state channels enabling selective molecular transport could potentially be used in a variety of separation and energy conversion applications. The density of channels, their height, distance and edge structure are the key factors that dramatically impact the selective transport performance. However, such channels with small constrictions and atomic precision have been limited to proof-of-concept demonstrations based on microscale two-dimensional (2D) crystal stripes. Here, we report the engineering of highly ordered, scalable monolayer graphene crystallite arrays by chemical vapor deposition (CVD) method with a modified anisotropic etching approach. The size, shape, distance and edge structure of the graphene crystallite arrays in a large area could be delicately controlled through tailoring the synthetic parameters. This array structure can act as pillars to prop up a smooth single-crystal graphene film, and the fabricated integrated angstrom-size (3.4 A) channels allow water transport but exclude hydrated ions, demonstrating potential in selective ionic sieving and nanofiltration practice.

The physical and chemical properties of transition metal dichalcogenides can be effectively tuned by doping or alloying, which is essential for their practical applications. However, the microstructure evolutions and their effects on the physical properties induced by alloying from hetero-atoms with different outermost electronic structures are still unclear. Here, we synthesized Nb-substituted WS2 with various Nb concentrations showing unusual changes of optical behaviors and continuous electrical polarity reversal. The fully softened Raman mode, rapidly quenched photoluminescence, and severe electron scattering can be attributed to the combined effects of charge doping and lattice strain caused by atomic Nb doping. Three types of substitution modes of Nb atoms in the WS2 lattice were observed directly from atomic-resolution scanning transmission electron microscopy. Density functional theory calculations further confirm the role of lattice strain in the evolutions of optical and electrical characteristics. With increasing Nb concentration, n-type, ambipolar, and p-type field-effect transistors can be achieved, indicating the capacity of this doping method to engineer the properties of two-dimensional materials for future electronic applications.

Two-dimensional (2D) materials as channel materials provide a promising alternative route for future electronics and flexible electronics, but the device performance is affected by the quality of interface between the 2D-material channel and the gate dielectric. Here we demonstrate an indium selenide (InSe)/hexagonal boron nitride (hBN)/graphite heterostructure as a 2D field-effect transistor (FET), with InSe as channel material, hBN as dielectric, and graphite as gate. The fabricated FETs feature high electron mobility up to 1,146 cm2V−1s−1 at room temperature and on/off ratio up to 1010 due to the atomically flat gate dielectric. Integrated digital inverters based on InSe/hBN/graphite heterostructures are constructed by local gating modulation and an ultrahigh voltage gain up to 93.4 is obtained. Taking advantages of the mechanical flexibility of these materials, we integrated the heterostructured InSe FET on a flexible substrate, exhibiting little modification of device performance at a high strain level of up to 2%. Such high-performance heterostructured device configuration based on 2D materials provides a new way for future electronics and flexible electronics.

Two-dimensional (2D) materials especially transition metal dichalcogenides (TMDs) have drawn intensive interests owing to their plentiful properties. Some TMDs with magnetic elements (Fe, Co, Ni, e...

We describe a method to obtain networks of wrinkles in multilayer graphene flakes (and other layered materials) by thermal contraction of the underlying PDMS substrate they are deposited on. The exfoliated flakes on PDMS are dipped into liquid nitrogen and after removal networks of wrinkles are found. The density of wrinkles can be controlled to some degree by sequential dipping into liquid nitrogen. Atomic force microscopy shows that wrinkles form preferentially along the armchair direction of the graphene lattice in such multilayer graphene platelets. Raman spectra show that the interlayer coupling at a wrinkle in multilayer graphene differs from, and is weaker than, that in undeformed regions. High resolution transmission electron microscopy measurements show that the interlayer distance increases in strained regions, which results in the interlayer coupling being decreased in particular regions of the wrinkles in these multilayer graphenes.

A graphene wrinkle is a quasi-one-dimensional structure and can alter the intrinsic physical and chemical activity, modify the band structure and introduce transport anisotropy in graphene thin films. However, the quasi-one-dimensional electrical transport contribution of wrinkles to the whole graphene films compared to that of the two-dimensional flat graphene nearby has still been elusive. Here, we report measurements of relatively high conductivity in micrometer-wide graphene wrinkles on SiO2/Si substrates using an ultrahigh vacuum (UHV) four-probe scanning tunneling microscope. Combining the experimental results with resistor network simulations, the wrinkle conductivity at the charge neutrality point shows a much higher conductivity up to ∼33.6 times compared to that of the flat monolayer region. The high conductivity can be attributed not only to the wrinkled multilayer structure but also to the large strain gradients located mainly in the boundary area. This method can also be extended to evaluate the electrical-transport properties of wrinkled structures in other two-dimensional materials.

The properties of two-dimensional (2D) van der Waals (vdW) materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here, we describe an assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition (CVD) growth, is best described using the analogy to Origami and Kirigami of paper and involves wrinkle formation, folding, tearing, and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of one-dimensional (1D) wrinkles into a 2D twist angle of a three-dimensional (3D) superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors, and super-conductors.

Sensors are routinely developed for specific applications, but multipurpose sensors are challenging, due to stability and poor functional design. We report organic materials that operate in solution and gas phase. They show a strong response behaviour to at least three types of environmental changes: pH, amine and metal ion binding/detection. We have confirmed and validated our findings using various analytical and computational methods. We found that the changes in polarity of the solvent and pH not only red shift the tail of the absorption spectra, but also extend the peak optical absorption of these structures by up to 100 nm, with consequential effects on the optical gap and colour changes of the materials. Acid–base response has been studied by spectrophotometric titrations with trifluoroacetic acid (TFA) and triethyl amine (TEA). The experiments show excellent reversibility with greater sensitivity to base than acid for all compounds. Analysis into metal sensing using Zn(II) and Cu(II) ions as analytes show that the materials can successfully bind the cations forming stable complexes. Moreover, a strong suppression of signal with copper gives an operative modality to detect the copper ion as low as 2.5 × 10−6 M. The formation of the metal complexes was also confirmed by growing crystals using a slow diffusion method; subsequent single crystal X-ray analysis reveals the ratio of ligand to metal to be 2 to 1. To test sensitivity towards various amine vapours, paper-based sensors have been fabricated. The sensors show a detection capability at 1 ppm of amine concentration. We have employed CIE L*a*b* colour space as the evaluation method, this provides numeric comparison of the samples from different series and allows comparison of small colour differences, which are generally undetectable by the human-eye. It shows that the CIE L*a*b* method can assess both sensitivity to a particular class of analytes and a specificity response to individual amines in this subclass offering an inexpensive and versatile methodology.

Andai therapy is a traditional therapy combining body, mind, and language with Mongolian characteristics. In the form of singing and dancing, it is widely popular among people of all ages in Mongolian areas of Inner Mongolia. According to Mongolian medicine, Heyi is one of the three elements of human body, and it can maintain life activities, promote blood circulation, and improve the functions of the sensory and mental consciousness. Andai therapy stimulates the whole body nerves and Heyi through music and dance, improves Heyi and blood operation, strengthens physique, improves immunity, effectively promotes physical and mental health, and plays a role in preventing and treating diseases. Objective. In this study, gas chromatography-mass spectrometry (GC-MS) was used to explore the mechanism of Andai therapy, so as to provide a new research direction for taking targeted prevention and treatment measures for diseases. Methods. Using gas chromatography-mass spectrometry (GC-MS) on all its cases baseline plasma to the targeted metabonomics testing, the differential metabolites of the experimental group (receiving Andai therapy) and control group (without receiving Andai therapy), analysis-related metabolite function, and screening of metabolites and related pathways through adjusting mechanism to explore the related factors are compared, to study the mechanism of the influence of Mongolian medical Andai therapy on the metabolism of different healthy people. Results. The differences in metabolic numbers between the experimental group and the control group are 114, such as cyclohexylamine chlorinated acid, 2,4-2 aminobutyric acid bitter almond alcohol, l-methyl inosine, 2-picolinate, and 2-hydroxy-2-glutaric acid metabolite content of the control group that are significantly higher than the experimental group, experimental group’s other substance content is significantly higher than that of the control group, and two groups’ metabolite content was obviously different. The number of differential metabolites between the female experimental group and the female control group was 119, and the number of differential metabolites between the male experimental group and the male control group was 48.

Studies have shown that the physical, psychological, and social problems of liver cancer patients are more serious than those of other cancer patients and their quality of life is significantly reduced. This may be related to the poor treatment effect of patients with advanced liver cancer. Patients often have adverse symptoms such as cancer pain, pleural effusion, and ascites, etc., which have a great impact on patients’ psychology and recovery from illness. With the change of the medical model, it has become history to rely solely on drugs to care for patients with advanced liver cancer and comprehensive nursing intervention has become very important. Continuous nursing intervention focuses on individualized and full-hearted care, effectively alleviating patients’ anxiety and fear and improving patients’ environmental adaptability and psychological defense mechanisms. However, in the field of liver cancer, there is no detailed comparison between the efficacy of continuous nursing and traditional conventional nursing. This article applies the hidden Markov model, starts with medical data mining, and describes the process achieved by the application of this article and the analysis of the results obtained by the two nursing methods, which reflect the difference in curative effect evaluation, and it proves that continuous nursing has more advantages in the curative effect of patients with liver tumors.

Dialdehyde sodium alginate (DSA) is an eco-crosslinker attracting extensive interest while undergoing limited large-scale applications. Herein, we employed DSA to react with dicyandiamide (DA) for engineering a biomass-derived retanning agent (BDR) towards addressing the long-term toxicity of residual formaldehyde (FA) in leather caused by amino resins. Results confirmed that BDR reserved the structural features of DSA by grafting DA onto DSA molecules. Owing to the suitable molecular weight (main components, 1424-1462 g/mol) and abundant oxygen-containing groups of BDR endowed by DSA, BDR-treated chrome-free leather showed higher hydrothermal stability (82.4 °C), thickening ratio (13.93 %), mechanical strengths (17.2 N/mm

We report the chemical vapor deposition (CVD) growth, characterization, and low-temperature magnetotransport of 1T phase multilayer single-crystalline VTe2 nanoplates. The transport studies reveal ...

From an energy-saving perspective, solar heat shielding materials for architectural or automobile glass have become more and more important for sustainable development, which has attracted global attention. The solar heat shielding materials need to meet the requirements of high visible transmittance, strong near infrared absorption, low cost and easy process. Nanostructured rare-earth hexaborides and tungsten bronzes are new kinds of promising heat shielding materials with excellent properties. This review presents a brief introduction on the recent progress in these two kinds of materials. Systematic work including the synthesis, characterization and optical response of nanocrystalline rare-earth hexaborides and tungsten bronzes are summarized. Especially the theoretical explanations of the mechanism of optical properties, tunable characteristic of optical properties, influence of particle size and shape on its optical response are reviewed in this document. Finally, we offer some suggestions for further investigation on these nanostructures, including efficient preparation methods considering environmental and economic costs for obtain morphology and size controllable samples; preventing agglomeration of the final products; some problems to be solved for commercial application. The review can provide a quick reference and overview for heat shielding materials and smart window industry.

SnS2 field effect transistor (FET) has been fabricated based on an exfoliated SnS2 flake. The effect of vacuum and sulfur-vapor annealing on the electric and optoelectronic properties of SnS2 FET have been investigated in detail. The experimental results indicate post-annealing, especially the sulfur-vapor annealing, has a strong impact on the electrical and photoelectric properties of SnS2 FET. The decreasing of source-drain current with annealing, the shift of threshold voltage and the exponential function of photocurrent varying with light intensity all exhibit a close relevance with surface states in SnS2. The intriguing characteristics can be well explained by sulfur-vacancies-related trapping mechanism. These results not only advance the current understanding of the generation, trapping and recombination behavior of photoexcited carriers in two-dimensional materials, but also stimulate the potential applications in optoelectronic devices based on SnS2.

With strong spin–orbit coupling (SOC), ultrathin two-dimensional (2D) transitional metal chalcogenides (TMDs) are predicted to exhibit weak antilocalization (WAL) effect at low temperatures. The ob...