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In the present work, tunable ferromagnetism can be introduced in NiTe2 crystals by Cr doping with high air-stability.

A GdAl3(BO3)4: Dy3+, Eu3+ phosphor was used for ratiometric optical thermometry based on different thermal sensitivities and energy transfer between Dy3+ and Eu3+.

A dual-mode immunoassay strategy based on CdS nanoparticles as signal probes with both of photoluminescent (PL) and multi-phonon resonance Raman scattering (MRRS) properties was developed. Simplified structural design and preparation were achieved due to the intrinsic integration of PL and MRRS dual signals in the single-unit CdS nanoprobes. Human immunoglobulin G (HIgG) was sensitively and specifically detected using the proposed PL-MRRS dual-mode strategy. The linear relationship between the HIgG concentration and the intensity of 707 nm PL peaks/300 cm

The absence of two-dimensional (2D) van der Waals (vdW) ferromagnetic crystals with both above-room-temperature strong intrinsic ferromagnetism and large perpendicular magnetic anisotropy (PMA) severely hinders practical applications of 2D vdW crystals in next-generation low-power magnetoelectronic and spintronic devices. Here, we report a vdW intrinsic ferromagnetic crystal Fe3GaTe2 that exhibits record-high above-room-temperature Curie temperature (Tc, ~350-380 K) for known 2D vdW intrinsic ferromagnets, high saturation magnetic moment (40.11 emu/g), large PMA energy density (~4.79 × 105 J/m3), and large anomalous Hall angle (3%) at room temperature. Such large room-temperature PMA is better than conventional widely-used ferromagnetic films like CoFeB, and one order of magnitude larger than known 2D vdW intrinsic ferromagnets. Room-temperature thickness and angle-dependent anomalous Hall devices and direct magnetic domains imaging based on Fe3GaTe2 nanosheet have been realized. This work provides an avenue for room-temperature 2D ferromagnetism, electrical control of 2D ferromagnetism and promote the practical applications of 2D-vdW-integrated spintronic devices.

Weyl semimetals haveattracted extensive research interests due to their unique topological properties. However, photoelectric devices based on pristine semimetals with large electrical conductivity...

Imaging-guided therapy is promising to improve glioma treatment in a personalized way. However, it is still challenging to develop appropriate multifunctional materials to overcome the limitations ...

The absence of two-dimensional (2D) van der Waals (vdW) ferromagnetic crystals with both above-room-temperature strong intrinsic ferromagnetism and large perpendicular magnetic anisotropy (PMA) severely hinders practical applications of 2D vdW crystals in next-generation low-power magnetoelectronic and spintronic devices. Here, we report a vdW intrinsic ferromagnetic crystal Fe

Luminescence-based methods are widely used for the detection of prostate specific antigen (PSA), for example during the diagnosis of prostate cancer. However, the accuracy of these methods is sub-optimal. The aim of this study was to develop an accurate and sensitive dual-mode immunosensing technique using a combination of resonance Raman scattering (RRS) and photoluminescence (PL) signals for the detection of PSA. A ZnS:Mn

Recently, the discussion about new candidate materials that can replace traditional Cu for future interconnects in integrated circuit (IC) fabrication attracts growing interests. In this paper, we have systematically investigated the breakdown current characteristic of a novel transition metal trichalcogenide (TMTCs) $\mathbf{ZrTe_{3}}$ by the finite element simulation. First, an electro-thermal coupling model was established, which the Joule heat of the $\mathbf{ZrTe_{3}}$ nanoribbon acts as the heat source, and both the solid heat transfer and the natural convection heat transfer are considered for the finite element simulation. Then, using the established model and experimental data, the breakdown temperature of the $\mathbf{ZrTe_{3}}$ nanoribbons in the air environment has been determined. Furthermore, the distribution of both temperature and current density of $\mathbf{ZrTe_{3}}$ nanoribbons during the breakdown process was investigated for failure analysis. Finally, according to the size-independent resistivity of TMTCs, the breakdown characteristic of the $\mathbf{ZrTe_{3}}$ with 10nm width was investigated by further finite element simulation. Its breakdown current density can reach 83.8 $\mathbf{MA}/\mathbf{cm}^{2}$ , which demonstrates the high potential of $\mathbf{ZrTe}_{3}$ nanoribbon as a new type of interconnects material of replacing copper interconnects.

The combination of semiconductivity and tunable ferromagnetism is pivotal for electrical control of ferromagnetism and next‐generation low‐power spintronic devices. However, Curie temperatures (T C) for most traditional intrinsic ferromagnetic semiconductors (≤200 K) and recently discovered two‐dimensional (2D) ones (, 2D van der Waals (vdW) semiconductor Cr x Ga1− x Te with highly tunable intrinsic room‐temperature ferromagnetism is realized and shows robust room‐temperature ferromagnetism with the 2D quantum confinement effect, enabling T C record‐high 314.9–329 K for 2D semiconductors. The M sat of vdW Cr x Ga1− x Te crystals can be effectively tuned up to ≈5.4 times by controlling Cr concentration and up to ≈75.9 times by changing the thickness.

Magnetic-optical nanocomposites, which consist of iron oxide nanoparticles and quantum dots, have aroused considerable research interest owing to their unique magnetic and luminescent properties. However, the luminescence of quantum dots tends to be quenched by the magnetic component. Resonant Raman scattering (RRS) of semiconductor nanocrystals, which originates from a strong electron-phonon interaction, provides a new candidate property to be exploited as an analytical tool. Herein, Fe3O4/ZnS nanocomposites were prepared with the seed-mediated growth approach. The nanocomposites exhibited superparamagnetism and characteristic multi-order phonon resonant Raman lines. By using biofunctionalized Fe3O4/ZnS nanocomposites as RRS probes, a femtomolar immunoassay of a model protein, human IgG, was realized with the assistance of an external magnetic field. The results provide guidance for the broad applications of magnetic-optical nanocomposites.

Quasi-one-dimensional (1D)/two-dimensional (2D) ZrTe3 attracts intense interest as a typical charge density wave (CDW)-bearing material. However, the conventional chemical vapor transport (CVT) synthesis of bulk ZrTe3 is limited by high time consumption, even up to weeks, and low morphological controllability, so it is highly desirable to develop feasible methods for fast and controlled ZrTe3 growth, and so far, these have not been demonstrated. In this work, we first demonstrated that ZrTe3 nanoribbons can be grown directly by a modified chemical vapor deposition (CVD) method. The growth time is significantly reduced to less than 90 min, and the size of ZrTe3 nanoribbons can be well tuned by controlling the growth time and growth temperature. Moreover, differing from most of the other transition metal trichalcogenides (TMTCs), we reveal that ZrTe3 nanoribbons exhibit both competing and synergistic magnetic properties originating from their intrinsic diamagnetism and unexpected ferromagnetism, which can be attributed to their structural imperfection and edge-states due to the reduced dimensionality. Such observable ferromagnetism might favor the exploration of their spin-electronic applications.

We demonstrated a feasible strategy to fabricate MoTe2/Ge heterojunction by direct growth of Ge flake on a MoTe2 film substrate with a two-step chemical vapor deposition method. A thin transition layer (∼4 nm) mainly composed of polycrystalline germanium at the MoTe2/Ge interface was verified during the Ge flake growth. The MoTe2/Ge heterojunction-based photodetector exhibits both the response speed with a rise/fall time of 7/4 μs and the photoresponsivity and detectivity with 4.87 A W−1 and 5.02 × 1011 Jones under zero bias in the near-infrared regime, respectively. The characteristics of device performance imply its practical applicability as building block for potential near-infrared integrated photonics.

We demonstrated that Schottky barrier height (SBH) at the metal/CVD-grown MoTe2 interface can be significantly reduced with tunnel contact by inserting a thin Al2O3 layer regardless of the metal work function. The existence of strong Fermi level pinning (FLP) at the metal/MoTe2 interface was verified, while depinning cannot be achieved with Al2O3 insertion. Thus, the fixed charges inside the Al2O3 were proposed to be responsible for the effective SBH reduction in virtue of the eliminated SBH reduction after the post-annealing treatment. This work provides a feasible way to solve the contact issue and favors for the fabrication of high performance MoTe2-based electronic devices.

The level of carcinoembryonic antigen (CEA) in serum has the significant reference value for early diagnosis and treatment of various cancers. However, the CEA detection still suffers from the issue of limited sensitivity and reliability. Herein, a fluorescence (FL)-infrared absorption (IRA) dual-mode nanoprobe was fabricated based on carbon dots (CDs)@SiO

In this paper, we focus on improving MoTe 2 nanoribbon MOSFETs device performance, with solution-processed HfAlOx high-k dielectric film compared with SiO 2 . First, 2H-MoTe 2 nanoribbons with high purity and quality were synthesized by CVD process. Then, solution-processed synthesis of HfAlOx thin film was systematically investigated. HfAlOx thin film obtained with 0.3M precursor concentration, annealing at 400°C in mixed gas of N 2 (95%) + H2(5%) showed low leakage current density and high k value. Finally, improved device performance of MoTe 2 nanoribbon transistors with mobility ~9.35 cm2V−1s−1, I on /I off ratio ~1.85×l05, and the threshold voltage ~ -3.52V were demonstrated.

Aiming to the ongoing challenge of accurate and sensitive detection for cancer biomarkers, antibody-functionalized NaYF4:Yb3+, Er3+@SiO2 nanorods were developed as upconversion luminescence (UCL)–infrared absorption (IRA) nanoprobes. Benefiting from the shielding effect of the SiO2 shell, an enhanced UCL was achieved. Additionally, an IRA detection signal was introduced by the Si-O-Si bonds of SiO2. Its mutual verification with UCL signal was favorable for ensuring the accuracy of the assay. A UCL-IRA sandwich detection method was established for the detection of the prostate-specific antigen. The UCL intensity at 542 nm and IRA at 1095 cm−1 were chosen for quantitative assay. The method has high sensitivity (0.05 pg mL−1) and selectivity. The range of detection (200 fg mL−1–200 ng mL−1) was singnificantly broadened compared with that of single-readout UCL or IRA detection. The assay performance of human serum samples demonstrated the practicability of the method in clinical cancer diagnosis.

The combination of semiconductivity and tunable ferromagnetism is pivotal for electrical control of ferromagnetism and next-generation low-power spintronic devices. However, Curie temperatures (TC ) for most traditional intrinsic ferromagnetic semiconductors (≤200 K) and recently discovered two-dimensional (2D) ones (

Solar desalination is an environment-friendly and sustainable technology to address the shortage of freshwater resources. However, it still faces huge challenges to develop a salt-rejection solar desalination system with continuous high efficiency. Herein, an electrospun nanofiber mat was fabricated for continuously high-efficiency solar desalination with carbon nanotube as a photothermal material, polyvinylidene fluoride as a floating support material and polyvinylpyrrolidone as a pore-forming agent. The porous structure and superhydrophilic surface provide significant water transport channels and thus avoid salt deposition, even in the high-salinity brine (20 wt% NaCl). The integration of strong broadband absorption property, excellent photothermal performance, floatability, durability and stability endows the solar desalination system with continuously high evaporation efficiency. The evaporation rate and solar conversion efficiency reached up to 1.372 kg m−2 h−1 and 86.1%, respectively, in simulated seawater under one sun irradiation and lasted for 11 h with little fluctuation. This work opens a new avenue for the rational design and fabrication of solar desalination systems to promote practical application.

We report the fabrication of high performance MoTe2/Si heterojunction photodiodes by direct growth of MoTe2 patterns on a commercial Si substrate by a feasible chemical vapor deposition method. The devices exhibit an ultrafast response speed with a rise/fall time of 5/8 μs, a broadband (400–1550 nm) photoresponse, a high on/off ratio of ∼104, and self-powered photo-detection with a zero bias responsivity of 0.26 A W−1 and a detectivity of 2 × 1013 Jones at 700 nm wavelength. The devices further show high stability in air for one month. This investigation offers the feasibility to fabricate high performance MoTe2/Si photodiodes for future vital optoelectronic applications.

The level of carcinoembryonic antigen (CEA) in serum has the significant reference value for early diagnosis and treatment of various cancers. However, the CEA detection still suffers from the issue of limited sensitivity and reliability. Herein, a fluorescence (FL)-infrared absorption (IRA) dual-mode nanoprobe was fabricated based on carbon dots (CDs)@SiO2 nanorod for CEA detection. The FL and IRA signals display no mutual interference and can verify each other, ensuring the reliability of assay results. The highly sensitive FL signal originating from the CDs is enhanced by the surface passivation of SiO2 and improves the overall sensitivity of the detection. The detection range spans 9 orders of magnitude and the limit of detection reaches 794.6 ag mL−1, which are great superior to the commercial kits and most of the previous reports. Satisfactory recovery over the commercial kits was achieved in real serum samples. The ultrasensitive and reliable FL-IRA detection strategy sheds light on a new avenue toward promoting the practicability of the nanoprobes in clinical cancer diagnosis.

A colorimetric method is described for the determination of Cu(II). It is based on branched polyethylenimine (BPEI) droplet evaporation on a superhydrophilic-superhydrophobic polystyrene micropatterned surface. Exposure to Cu(II) leads to a color change from colorless to light blue and dark blue. The micropatterned surface was fabricated via combining electrospinning with oxygen plasma and served as a detection substrate. Analysis requires only a single drop of blood. The method has a linear response in the 5.0 μM to 2.5 mM Cu(II) concentration range which is within the physiological range (15.7 ∼ 23.6 μM). Compared to an assay in solution, the detection limit is decreased from 386 nM to 89 nM. Excellent selectivity over other metal ions and anions was achieved. Graphical abstract A rapid and sensitive colorimetric detection platform for Cu(II) was fabricated by using branched-polyethylenimine droplet evaporation on a superhydrophilic-superhydrophobic micropatterned surface. Only a single drop of blood was needed for the analysis. The sensitivity was improved about 4.3 times.

High performance liquid chromatography (HPLC) has been widely considered as the most effective way for the separation and preparation of optically pure enantiomers. In the resolution by HPLC, the separation ability of a column strongly depends on the properties of a chiral stationary phase (CSP). Among many CSPs, the immobilized CSPs, which are becoming one of the most important kinds of CSPs, have the advantages of good solvent durability and enormous method flexibility. In this work, a novel optically active acrylamide derivative (S)-APACP was synthesized by two-step reactions, and its chemical structure was characterized by 1H NMR. The polyacrylamide derivatives were immobilized on silica gel by three-step reactions to prepare immobilized CSPs, and the immobilization amount of the polymers was tested by thermogravimetric analysis. The chiral recognition ability of the immobilized CSPs was evaluated by HPLC, and the effects of Lewis acid and mobile phase on the chiral recognition ability were investigated. The results showed that APACP polymer was successfully immobilized on silica gel to prepare immobilized-type CSP with better solvent durability, and the amount of immobilized polymer was 10. 2% to 11. 8%. The immobilized-type CSP showed good chiral recognition ability for several enantiomers.