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Abstract: A series of red-emitting Eu3+-doped K2LaNb5O15 niobate phosphors with tetragonal tungsten bronze-type structure were synthesized by the solid state reaction method. The structure of new tungsten bronze-type K2EuNb5O15 was identified by Rietveld refinements to crystallize in the tetragonal space group P4bm, which is isostructural to K2LaNb5O15. The relative intensity of the emission from both 5D0→7F2 and 5D0→7F1 increases with increasing Eu3+ ion concentration. The quenching mechanism of the K2La1−x Nb5O15:xEu system was investigated in detail. The relationship between Photoluminescence properties and the TTB-type structure was discussed. The quantum efficiency of K2EuNb5O15 excited under near-UV light (399nm) is 132% of that of commercial Y2O3:Eu3+ (394nm). The results demonstrated K2EuNb5O15 phosphor as a potential candidate for white light emitting diode pumped by near-UV or blue chip. [Copyright &y& Elsevier]

Abstract: A series of red-emitting Eu3+-doped phosphors SrLa2Mg2W2O12 were successfully prepared by the solid state reaction and their luminescence properties were investigated in detail. Under 464nm light excitation, the emission intensity at 613nm increased with the Eu3+ ion concentration rising, and the quenching effect did not appear until the Eu3+ ion concentration reached 25%, and the critical distance was calculated to be 7.74Å. The emission intensity of Sr(La0.75Eu0.25)2Mg2W2O12 is approximately three times higher than that of the commercial red phosphor Y2O3:Eu3+ under the blue light, meanwhile, the quantum efficiency of Sr(La0.75Eu0.25)2Mg2W2O12 is about two times higher than that of Y2O3:Eu3+. The Commission Internationale de l′Eclairage chromaticity coordinate of Sr(La0.75Eu0.25)2Mg2W2O12 is (x=0.660, y=0.340), which is closed to the standard of NTSC (x=0.670, y=0.330). The results indicate that Sr(La1−x Eu x )2Mg2W2O12 could be a potential red phosphor in fabrication of blue chips WLEDs. [Copyright &y& Elsevier]

Abstract: Hydrothermal synthesis, characterization and magnetic properties of a series of ABO3-perovskites LaFe1−x Cr x O3 (0≤x≤1) are reported. The alkalinity in initial reaction mixtures plays a critical role in controlling the designed stoichiometry of the final compositions. Their magnetic properties are strongly dependent on the compositions and a maximum magnetic moment is found for the sample at x=0.5. Weak ferromagnetic interaction observed for the samples from x=0 to 0.9 arises from the presence of Fe–O–Fe antisymmetric exchange and Fe–O–Cr superexchange interaction. The weak ferromagnetism as well as the linear variation of the lattice parameters implies the possible random distribution of Fe and Cr ions in B sites of the perovskites. The evolution of magnetic ordering transition temperatures has a close relationship with substituent ratios, for the competition of antiferromagnetism and ferromagnetism. The saturated magnetic moment shows a great improvement compared with that for the samples synthesized by solid state method. [Copyright &y& Elsevier]

Abstract: The calcium-doped manganates, Pr1− x Ca x MnO3 (x=0.39, 0.46, 0.70, 0.76), were synthesized as cube-shaped crystalline phases under mild hydrothermal conditions for the first time. The crystals could be grown in one step from solutions of metal salts and potassium hydroxide at temperatures ∼240°C, and found to adopt perovskite-like structure (space group Pbnm). Samples were characterized by powder X-ray diffraction, scanning electron microscopy, inductively coupled plasma analysis and variable temperature dc/ac magnetic susceptibility. The studies indicate that formation of the materials is dependent on the alkalinity and composition of the initial reaction mixtures. The magnetic properties show spin-glass-like behavior due to competing ferromagnetic (FM) and antiferromagnetic (AFM) exchange interactions in Pr1− x Ca x MnO3 with , 0.46. [Copyright &y& Elsevier]

Purpose: Bladder cancer (BLCA) is a highly heterogeneous tumor. We aim to construct a classifier from the perspective of N6-methyladenosine methylation (m6A) to identify patients with different prognostic risks and treatment responsiveness for precision therapy. Methods: Data on gene expression profile, mutation, and clinical characteristics were mainly obtained from the TCGA-BLCA cohort. Unsupervised clustering was performed to construct m6A subtypes. The tumor microenvironment (TME) landscapes were explored by using ssGSEA, ESTIMATE, and MCPcounter algorithms. K-M survival curves and Cox regression analysis were used to demonstrate the significance of m6A subtypes in predicting prognosis. pRRophetic, oncoPredict, and TIDE algorithms were used to evaluate responsiveness to antitumor therapy. A classifier of m6a subtypes was finally developed based on random forest and artificial neural network (ANN). Results: The two m6A subtypes have significantly different m6A-related gene expression profiles and mutational landscapes. TME analysis showed a higher level of stromal and Inhibitory immune components in subtype B compared with subtype A. The m6A subtype is a clinically independent prognostic predictor of BLCA, subtype B has a poorer prognosis. Drug sensitivity analysis showed that subtype B has lower IC50 values and AUC values for cisplatin and docetaxel. Efficacy assessment showed significantly poorer radiotherapy efficacy and lower immunotherapy responsiveness in subtype B. We finally constructed an ANN classifier to accurately classify BLCA patients into two m6A subtypes. Conclusion: Our study developed a classifier for identifying subtypes with different m6A characteristics, and BLCA patients with different m6A subtypes have significantly different prognosis and responsiveness to antitumor therapy., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Single-component white-light luminescent materials are considered an economical and facile choice for phosphor-converted white light-emitting diodes (pc-WLEDs). Here, a new single-component white-light-emitting material Cs 2 MnCl 4 :Eu 2+ based on the combination of a lead-free halide structure and a rare-earth ion is first reported. Benefiting from the smart dilution-sensitization design strategy, white light composed of dual broad emission originating from Eu 2+ (blue light, 444 nm, 4f 6 5d 1 → 4f 7 ) and Mn 2+ (yellow light, 566 nm, 4 T 1g → 6 A 1g ) was successfully realized under near-ultraviolet light (404 nm) radiation with a high photoluminescence quantum yield of 66%. Based on the single-source Cs 2 MnCl 4 :Eu 2+ phosphor, a pc-WLEDs device with "eye-friendly" white light production was successfully fabricated. The pc-WLEDs exhibit suitable color coordinates of (0.3294, 0.2746) and a high color rendering index of 82.3, demonstrating the potential in the future health-conscious illumination application by reducing the risk of eye strain and high-energy blue-light damage. This work achieves a new single-component white-light-emitting Mn-based halide phosphor and provides a new path for the design of single-component white light sources in Mn-based halides.

A green phosphor Sr 2 ZnGe 2 O 7 :Mn 2+ with a melilite structure was prepared using a high-temperature solid-state reaction. When the 535 nm emission was monitored, the excitation spectrum of the Sr 2 ZnGe 2 O 7 :Mn 2+ was found to contain two excitation bands in the ultraviolet (UV) region. When excited by UV light, the sample shows bright green emission at 535 nm, which corresponds to the distinctive transition of Mn 2+ ( 4 T 1 → 6 A 1 ). Moreover, the quantum efficiency of Sr 2 ZnGe 2 O 7 :Mn 2+ could reach 67.6%. Finally, a high-performance white-light-emitting diode (WLED) with a low correlated colour temperature of 4632 K and a high colour rendering index (CRI) of 92.3 were packaged by coating commercial blue and red phosphors with an optimized Sr 2 ZnGe 2 O 7 :Mn 2+ sample on a 310 nm UV chip. This indicated that Sr 2 ZnGe 2 O 7 :Mn 2+ has the potential application as a green component in the WLED lighting field., (© 2023 John Wiley & Sons Ltd.)

Atomically thin two-dimensional (2D) bismuth oxychalcogenides have been considered as promising candidates for high-speed and low-power photoelectronic devices due to their high charge carrier mobility and excellent environmental stability. However, the photoelectric performance of their bulk materials still falls short of expectations. Herein, a novel Bi 9 O 7.5 S 6 /SnS composite film with a type-II heterojunction was successfully prepared by combining hydrothermal and knife-coating techniques. The crystal structure, morphology, and optical properties were systematically investigated. Under 1 V bias voltage, the photocurrent of the Bi 9 O 7.5 S 6 /SnS composite film can be obtained as 107 μA cm -2 , which is about 29.9 times and 93.9 times higher than that of bare Bi 9 O 7.5 S 6 and SnS, respectively. The type-II heterojunction has played a significant role in improving the photoelectric performance of the Bi 9 O 7.5 S 6 /SnS composite film by facilitating the separation and transfer of photo-generated carriers. This work sheds light on the design and development of new bismuth-based composite materials for advanced photoelectric and photocatalytic applications.

Layered bismuth oxychalcogenides have been demonstrated as potential candidates for high-speed and low-power electronics due to their outstanding environmental stability and high carrier mobility, but the photoelectric performance of bulk species is still far from satisfactory. Herein, a novel Bi 9 O 7.5 S 6 /CdS composite film with a type-II heterojunction has been successfully prepared by combining chemical bath deposition (CBD) and spin-coating technologies. The structure, morphology, optical and photoelectric properties of the samples were investigated systematically. The photoelectric current of the Bi 9 O 7.5 S 6 /CdS composite film was obtained as 32.49 μA cm -2 at 1 V, which is about 13.9-fold and 3.3-fold higher than those of bare Bi 9 O 7.5 S 6 and CdS. An enhanced photoelectric response and photostability were achieved in the Bi 9 O 7.5 S 6 /CdS composite film, and can be appropriately attributed to the improved separation and transfer of photogenerated carriers driven by the type-II heterojunction. This work offers a promising route to develop high-performance visible-light photoelectric devices with type-II heterojunctions.

With the aim of improving the photocatalytic activity for water splitting, novel core-shell-structured crystalline-BaTiO 3 /amorphous-BaTiO 3-x /crystalline-CdS composite nanocubes are prepared by a facile two-step synthesis approach. Basic characterization techniques such as X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy are carried out on the as-prepared composite nanocubes in order to confirm the quality of their crystal structure, morphology and chemical components correspondingly. UV-Vis-NIR measurements of the as-prepared composite nanocubes validate the presence of extended visible-light absorbance due to oxygen-deficient BaTiO 3-x . Photoelectrochemical tests are carried out on the as-prepared nanocomposite films that are coated directly on indium tin oxide (ITO) glass substrates. The as-prepared composite nanocubes show a photocurrent density of 100 μA cm -2 without electric field poling, whereas they show about 200 μA cm -2 with an electric field poling of 18.8 kV cm -1 . This study suggests that the photoelectrochemical performance is highest in our prepared BaTiO 3 /BaTiO 3-x /CdS composite film compared to the pure BaTiO 3 , CdS and BaTiO 3 /BaTiO 3-x films, and it may offer a new potential route for designing cost-effective, highly stable and efficient photocatalysts.

Layered transition-metal chalcogenides have attracted great interest due to their unique electronic and optical properties. Here, we represent two layered quaternary chalcogenides K2CoCu3S4 and K2CoCu3Se4 prepared by a convenient hydrothermal route. From powder XRD and TEM analyses, K2CoCu3Q4 possesses a tetragonal ThCr2Si2-type structure with a random arrangement of Co and Cu atoms. The phase purity of the samples was confirmed by ICP, SEM, and EDS analyses, and the oxidation states of Co and Cu atoms were determined to be +3 and +1 by XPS spectra. Both samples show a weak ferromagnetic behavior at low temperature induced by spin-canted antiferromagnetic ordering. The temperature dependent resistivity, ρ(T), reveals a metallic nature for stoichiometric K2CoCu3S4. The semiconducting behavior of K2CoCu3Se4 could be explained better by variable range hopping (VRH) rather than adiabatic small polaron hopping (SPH). This new series of layered chalcogenides may offer a promising candidate for potential electronic applications.

Enhanced solar light absorption and photocatalytic and photoelectrochemical properties have been achieved in black BaTiO 3 with a unique core/shell structure (crystalline BaTiO 3 @amorphous BaTiO 3-x ) using an Al-reduction method. This finding may open a new avenue to tune the inert ferroelectric materials toward excellent photocatalysts for advanced applications.

A new series of mixed valence perovskites, La 0.75 K 0.25 AMnTiO 6 (A = Sr and Ba) nanocubes, have been synthesized by a mild hydrothermal route. From powder X-ray diffraction (XRD) analysis, the crystal structure of La 0.75 K 0.25 AMnTiO 6 was solved as the orthorhombic symmetry (space group Pbnm) with a random A-site or B-site arrangement. The phase purity of the products was confirmed by ICP, SEM, and EDS analyses, and the oxidation states of the B-site metal atoms were determined to be +4 for Ti and +3/+4 for Mn from XPS results. The soft ferromagnetic behavior is present in both samples. The Curie point T C has been detected as high as 309 K in La 0.75 K 0.25 SrMnTiO 6 and 217 K in La 0.75 K 0.25 BaMnTiO 6 . A Griffiths phase can be observed at the high temperature region, which is related to the magnetic inhomogeneity induced by the existence of short-range ferromagnetic clusters. The resistivity measurements indicate that the semiconducting properties of the samples can be depicted better by variable range hopping (VRH) due to a diluted double-exchange interaction of Mn 3+ -O-Mn 4+ with Ti 4+ doping.

La1-xMgxO1-2xF2xBiS2 (x = 0.1-0.35) were synthesized, and their superconductive properties were investigated. The superconducting transition temperature (Tc) increased below the codoping level (x ≤ 0.25). La1-xMgxOBiS2 (x = 0-0.2) and La1-xMgxO0.6F0.4BiS2 (x = 0.1-0.3) were further prepared to explore the effect of Mg(2+). We found that the introduction of Mg(2+) and F(-) leads to local structure distortion. Larger distortion is beneficial for superconductivity in LaOBiS2, which was further confirmed by the results in La1-xCaxO1-2xF2xBiS2 (x = 0.2, 0.3).