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CsPbBr3 exhibits strong green emission, but its toxicity limits its widespread application. Lead-free perovskites exhibit excellent optoelectronic properties while eliminating the toxicity of lead; at the same time, doping substitution is an effective means to further optimize the optoelectronic performance of perovskites. In this work, zinc(II) is chosen to achieve heterovalent substitution in the copper(I) based perovskite Cs3Cu2Cl5 and obtain strong green luminescence. The photoluminescence quantum yield (PLQY) reached 70.19% at an optimal doping concentration, which is twice the PLQY of undoped Cs3Cu2Cl5 and much higher than that of most doped lead-free perovskites. Furthermore, a white light emitting diode (WLED) was fabricated with doped Cs3Cu2Cl5:0.20 Zn2+ as a green phosphor, commercial blue phosphor Sr(PO4)Cl:Eu+, and commercial red phosphor CaAlSiN3:Eu2+. The color rendering index (CRI) is 95.8, while the correlated color temperature (CCT) is 4573 K, which is much better than that of the WLED fabricated with CsPbBr3. This research provides important guidance on the fabrication of green light emission Zn-doped Cs3Cu2Cl5 instead of toxic CsPbBr3 and has potential in WLED lighting. [ABSTRACT FROM AUTHOR]

A novel Mn2+ doped ScTaO4 phosphor was synthesized through a high temperature solid state method and its photoluminescence properties were systematically investigated. The ScTaO4:Mn2+ phosphor exhibited two emission bands centered at 478 nm and 661 nm under UV excitation, attributed to the self-activated emission of the host and the 4T1 → 6A1 transition emission from doped Mn2+ ions, respectively. Through optimizing the concentration of doped Mn2+ ions, white light emission was achieved. Meanwhile, the temperature-dependent luminescence spectra of the ScTaO4:Mn2+ phosphor (in the range from 298 K to 523 K) revealed significantly different thermal quenching behaviors between the host and Mn2+ ions, which cause a notable change in the fluorescence intensity ratio of the host versus Mn2+ ions and enable high absolute and relative sensitivities, with maximum values of 0.0172 K−1 and 2.1% K−1 at 523 K, respectively. The results indicated that the as-prepared STO:Mn2+ phosphor can be a potential candidate material for high temperature optical thermometry. [ABSTRACT FROM AUTHOR]

Transition metal ion and/or rare earth ion doped CsPbCl3 nanocrystals (NCs) have attracted extensive attention due to their high combined emission efficiency characteristics. Their high-throughput preparation is of great significance for future industrialization that is still a challenge based on existing batch reaction technologies. Herein, we demonstrate a high-throughput preparation method of Mn2+-doped CsPbCl3 NCs based on a fluidic channel reactor. The as-prepared NCs show vivid yellowish-orange emission at 600 nm and high photoluminescence quantum yield (PLQY) of 63.3%. Meaningfully, due to the closer bond between surface ligands and NCs, NCs prepared by this method show better water durability than NCs obtained using the traditional hot injection method. Finally, a WLED with a high color rendering index (CRI) of 94 and a low correlated color temperature (CCT) of 3626 K was fabricated by combining the as-prepared yellowish-orange Mn-doped CsPbCl3 with the BaMgAl10O17:Eu2+ (BAM:Eu2+) blue phosphor and CaAlSiN3:Eu2+ (CASN:Eu2+) red phosphor on a 375 nm ultraviolet chip. These findings suggest that the Mn-doped CsPbCl3 prepared by the fluidic channel reaction is suitable for WLEDs. Our work paves the way for achieving a continuous, large-scale preparation of perovskite NCs by a fluidic channel reaction for the development of their WLED solid state lighting applications. [ABSTRACT FROM AUTHOR]

A green phosphor Sr2ZnGe2O7:Mn2+ 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 Sr2ZnGe2O7:Mn2+ 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 Mn2+ (4T1→6A1). Moreover, the quantum efficiency of Sr2ZnGe2O7:Mn2+ 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 Sr2ZnGe2O7:Mn2+ sample on a 310 nm UV chip. This indicated that Sr2ZnGe2O7:Mn2+ has the potential application as a green component in the WLED lighting field. [ABSTRACT FROM AUTHOR]

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 Bi9O7.5S6/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 Bi9O7.5S6/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 Bi9O7.5S6 and SnS, respectively. The type-II heterojunction has played a significant role in improving the photoelectric performance of the Bi9O7.5S6/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. [ABSTRACT FROM AUTHOR]

Background: Uterine corpus endometrial carcinoma (UCEC) is a gynecological malignant tumor with high incidence and poor prognosis. Although immunotherapy has brought significant survival benefits to advanced UCEC patients, traditional evaluation indicators cannot accurately identify all potential beneficiaries of immunotherapy. Consequently, it is necessary to construct a new scoring system to predict patient prognosis and responsiveness of immunotherapy. Methods: CIBERSORT combined with weighted gene co-expression network analysis (WGCNA), non-negative matrix factorization (NMF), and random forest algorithms to screen the module associated with CD8+ T cells, and key genes related to prognosis were selected out by univariate, least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses to develop the novel immune risk score (NIRS). Kaplan–Meier (K-M) analysis was used to compare the difference of survival between high- and low- NIRS groups. We also explored the correlations between NIRS, immune infiltration and immunotherapy, and three external validation sets were used to verify the predictive performance of NIRS. Furthermore, clinical subgroup analysis, mutation analysis, differential expression of immune checkpoints, and drug sensitivity analysis were performed to generate individualized treatments for patients with different risk scores. Finally, gene set variation analysis (GSVA) was conducted to explore the biological functions of NIRS, and qRT-PCR was applied to verify the differential expressions of three trait genes at cellular and tissue levels. Results: Among the modules clustered by WGCNA, the magenta module was most positively associated with CD8+ T cells. Three genes (CTSW, CD3D and CD48) were selected to construct NIRS after multiple screening procedures. NIRS was confirmed as an independent prognostic factor of UCEC, and patients with high NIRS had significantly worse prognosis compared to those with low NIRS. The high NIRS group showed lower levels of infiltrated immune cells, gene mutations, and expression of multiple immune checkpoints, indicating reduced sensitivity to immunotherapy. Three module genes were identified as protective factors positively correlated with the level of CD8+ T cells. Conclusions: In this study, we constructed NIRS as a novel predictive signature of UCEC. NIRS not only differentiates patients with distinct prognoses and immune responsiveness, but also guides their therapeutic regimens. [ABSTRACT FROM AUTHOR]

Oxygen-deficient TiO2-based composites have attracted widespread attention due to their promoted light-harvesting capacity and energy conversion efficiency, beneficial for water splitting. Despite being a facile, secure-safe and undefiled route for preparing blackened TiO2, the Al-reduction method has not been adopted for preparing TiO2/TiO2−x/CdS composite films. Herein, TiO2/TiO2−x/CdS composite nanorods were successfully fabricated by combining hydrothermal, Al-reduction and chemical bath deposition (CBD) techniques. Enhanced visible-light absorption and photoelectrochemical performances have been achieved using TiO2/TiO2−x/CdS heterojunction nanorods. The photocurrent density of TiO2/TiO2−x/CdS was obtained to be 7.75 mA cm−2 at 0 V vs. Ag/AgCl under AM 1.5 G illumination, which was 77.5-fold and 12.1-fold higher than those of bare TiO2 and CdS, respectively. This work may offer new insights for realizing TiO2-based composites with improved solar absorption for photoelectrochemical applications. [ABSTRACT FROM AUTHOR]

Low-dimensional metal halides have attracted extensive attention because of their superior optoelectronic properties, high stability and structural diversity. In this work, we report a two-dimensional (2D) lead-free halide Cs2MnCl4:Cu+ as a new phosphor for white light-emitting diodes (LEDs). By doping copper(I) into manganese(II) sites, a strong green emission with a photoluminescence quantum yield (PLQY) of 70% was observed. The luminescence center was located at 530 nm and the optimal excitation wavelength was determined to be 310 nm, which suggests a large Stokes shift of 220 nm. Steady-state and transient fluorescence spectra show a decay time of 114.19 μs, indicating a self-trapped exciton (STE) emission mechanism which was further confirmed by temperature-dependent steady-state photoluminescence spectroscopy. This work suggests that manganese halides could be considered as a new family with high luminescence efficiency for optoelectronic applications. [ABSTRACT FROM AUTHOR]

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 Bi9O7.5S6/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 Bi9O7.5S6/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 Bi9O7.5S6 and CdS. An enhanced photoelectric response and photostability were achieved in the Bi9O7.5S6/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. [ABSTRACT FROM AUTHOR]

White light emitting diodes (LEDs) suffer from two most common drawbacks: the deficiency of the red component and the poor thermal stability of silicone. Ce3+-doped garnet phosphors with tailor-made luminescence properties can be achieved by variations in {A}, {B}, and {C} cation sites. Herein, a simultaneous ion co-substitution design strategy has been adopted to synthesize a series of (Y, Ca)3(Al, Mg)2(Al, Si)3O12 garnet phosphors and corresponding phosphor-in-glass (PiG) films. The co-substitution is finely restricted to the assigned sites. The emission peak is shifted from 529 to 565 nm, which is beneficial to obtain low color temperatures and high color rendering using a single phosphor for white LEDs. By employing the as-synthesized phosphor, the corresponding PiG films were fabricated by the low temperature co-sintering technology using the SiO2–B2O3–ZnO–Na2O glass system characterized with excellent thermal stability and moisture resistance. The morphological and elemental analyses demonstrated that the as-made phosphor powders were uniformly distributed in the glass host without any interfacial reactions. Finally, modular white LEDs with a high color rendering (Ra = 82.7) is achieved through the as-synthesized PiG film on an InGaN blue chip. This study may open up a facile approach to obtain high quality luminescence based on the mono-luminescence center, avoiding excitation energy wastage and low quantum efficiency aroused by multi-luminescence centers or color compensation phosphors in glass. [ABSTRACT FROM AUTHOR]

Using a green and convenient method to prepare fluoride red phosphor is an important challenge for industrialization applications. In this work, K2SiF6:Mn4+ red phosphor was successfully prepared through a brief one-step co-precipitation method without HF. A simplified and non-toxic ion exchange strategy for the formation of narrow-band red-emitting K2SiF6:Mn4+ phosphors was developed using different solvent (HAc, H3PO4, HNO3, HCl, H2O). The photoluminescence intensity of the prepared K2SiF6:Mn4+ red phosphor was the highest when the pH of the reaction solution was 1.0. Furthermore, using K2SiF6:Mn4+ as red component, the warm white light LED (light-emitting diode) with low correlated color temperature (CCT = 4095 K), high color rendering index (CRI, Ra = 87) was achieved, which proved that the phosphor synthesized by this method had great application potential. The preparation method provided in this article is safer and more environmentally friendly, and has important commercial and social value. [ABSTRACT FROM AUTHOR]

A novel quaternary oxysulfide, FeOCuS has been successfully synthesized with a tetragonal anti-PbO-type structure and a visible-light bandgap of about 1.37 eV. Driven by only a 0.4 V bias voltage under simulated AM 1.5 G illumination, a high photocurrent density of 3.89 mA cm−2 has been achieved, revealing the potential optoelectronic applications. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have shown great promise as transparent conductive films (TCFs) due to their excellent optoelectronic performance. In order to replace indium tin oxide (ITO), considerable intricate methods have been adopted in combination, thus largely restricting their large-scale applications. Currently, it remains a concern that the research on AgNWs-based TCFs is still required great efforts to balance the high optical transparency and low resistance simultaneously. Here, we deposited AgNWs network onto silica nanospheres (SNSs) antireflection (AR) layer via a facile solution method. The assembled SNSs structure can effectively reduce reflection of the substrate. AgNWs-based composite TCFs achieve optical transmittance of 99.84%, elevating the transmittance by 6.94% with the sheet resistance reaching 49.43 Ω sq−1 declined by 8.66% compared to the pristine AgNWs film. Due to the surface adsorption of nanospheres and the mutual electrophilic effect, the interaction between AgNWs and SNSs is strong, hence exerting the synergetic effect on optoelectronic performance. Furthermore, the results have demonstrated that SNSs AR nanostructure contributes to moderating the interface property of pristine AgNWs film, indicating that it is favorable to ameliorate the impact of increased surface roughness stemming from the interwoven nanowires network structure. The whole solution-processed AgNWs/SNSs composite films in our work bring about great potential engineering for transparent conductors or other optoelectronic devices. [ABSTRACT FROM AUTHOR]

With the aim of improving the photocatalytic activity for water splitting, novel core–shell-structured crystalline-BaTiO3/amorphous-BaTiO3−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 BaTiO3−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 BaTiO3/BaTiO3−x/CdS composite film compared to the pure BaTiO3, CdS and BaTiO3/BaTiO3−x films, and it may offer a new potential route for designing cost-effective, highly stable and efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Ferroelectric photovoltaics, as a new type of solar cell, relying on an internal electric field instead of p–n or Schottky junctions, can considerably improve the efficiency of charge separation and migration. But, non-volatile elements containing ferroelectrics with narrow bandgaps and excellent photoelectric performances are still scarce. Herein, a new ferroelectric compound, BaFe4O7, has been synthesized by a conventional hydrothermal method. A polar trigonal structure (P31c) was proposed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses. UV-vis-NIR diffuse reflectance spectrum revealed a visible-light bandgap Eg of 2.18 eV. Intrinsic ferroelectricity with a high Curie temperature (Tc ∼ 791 K) was confirmed by dielectric and ferroelectric measurements. The electrical saturation polarization (Ps), remanent polarization (Pr) and coercive field (Ec) were determined as 6.34 μC cm−2, 3.32 μC cm−2 and 42.38 kV cm−1 respectively. A bulk photovoltaic effect was observed in the poled sample with a steady-state photocurrent of 39 nA cm−2 and photovoltage of 0.19 V under standard AM 1.5G illumination, which demonstrated its promising applications in photoelectric devices. [ABSTRACT FROM AUTHOR]

The performance of graphene transparent conductive films (TCFs) can be greatly enhanced by introducing an antireflection (AR) nanostructure. We directly deposited graphene on silica nanosphere/acid-catalyzed silica layer (SNS/a-SL) AR nanostructure by assisted catalysis of Cu nanoparticles in ambient pressure chemical vapor deposition to obtain graphene composite TCFs. By introducing the SNS/a-SL AR nanostructure, the transmittance and sheet resistance of graphene TCFs achieved were 89.65% and 2.04 kΩ sq−1, respectively. Compared to graphene films, the transmittance was improved by 5.5% and sheet resistance was reduced by 0.44 kΩ sq−1. The SNS/a-SL AR nanostructure effectively reduced reflection from the substrates owing to the structure of gradient refractive index and exhibited good stability at high temperatures because of the existence of a-SL. The AR nanostructure also could provide more electronic transport channels to achieve regulation of the electrical property of graphene TCFs. This method simultaneously improves the transmittance and conductivity of graphene TCFs by a facile process, providing an important method to prepare graphene TCFs with excellent performance. [ABSTRACT FROM AUTHOR]

Layered bismuth oxychalcogenides have been considered exciting material systems with potential applications in superconductivity and thermoelectricity, but their optoelectronic properties still require greater diligence. The pressure-driven 2D–3D structural reconstruction is an efficient strategy to in situ tune the electronic configuration of functional materials, and yet has remained a challenge for both fundamental studies and technological applications. Here, we present the pressure-driven buckling effects of the layered bismuth oxysulfide Bi9O7.5S6 on a 3D network structure. Although no crystallographic symmetry change was observed up to 58.1 GPa, the layer and bonding distances between and within BiO and BiS layer changed dramatically, which drives the enhancements of electric conductivity by 6 orders of magnitude, increasing the photocurrent by 4 orders of magnitude, and significant narrowing down of band gap from 1.34 eV to 0.45 eV. These findings may open a new avenue for discovering and designing high-efficiency photodetectors and energy-harvesting materials. [ABSTRACT FROM AUTHOR]