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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]

Background: Hepatocellular carcinoma (HCC) is a highly prevalent and deadly cancer, with limited treatment options for advanced-stage patients. Disulfidptosis is a recently identified mechanism of programmed cell death that occurs in SLC7A11 high-expressing cells due to glucose starvation-induced disintegration of the cellular disulfide skeleton. We aimed to explore the potential of disulfidptosis, as a prognostic and therapeutic marker in HCC. Methods: We classified HCC patients into two disulfidptosis subtypes (C1 and C2) based on the transcriptional profiles of 31 disulfrgs using a non-negative matrix factorization (NMF) algorithm. Further, five genes (NEIL3, MMP1, STC2, ADH4 and CFHR3) were screened by Cox regression analysis and machine learning algorithm to construct a disulfidptosis scoring system (disulfS). Cell proliferation assay, F-actin staining and PBMC co-culture model were used to validate that disulfidptosis occurs in HCC and correlates with immunotherapy response. Results: Our results suggests that the low disulfidptosis subtype (C2) demonstrated better overall survival (OS) and progression-free survival (PFS) prognosis, along with lower levels of immunosuppressive cell infiltration and activation of the glycine/serine/threonine metabolic pathway. Additionally, the low disulfidptosis group showed better responses to immunotherapy and potential antagonism with sorafenib treatment. As a total survival risk factor, disulfS demonstrated high predictive efficacy in multiple validation cohorts. We demonstrated the presence of disulfidptosis in HCC cells and its possible relevance to immunotherapeutic sensitization. Conclusion: The present study indicates that novel biomarkers related to disulfidptosis may serve as useful clinical diagnostic indicators for liver cancer, enabling the prediction of prognosis and identification of potential treatment targets. [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: Doxorubicin (DOX)-induced cardiotoxicity (DIC) is a major impediment to its clinical application. It is indispensable to explore alternative treatment molecules or drugs for mitigating DIC. WGX50, an organic extract derived from Zanthoxylum bungeanum Maxim, has anti-inflammatory and antioxidant biological activity, however, its function and mechanism in DIC remain unclear. Methods: We established DOX-induced cardiotoxicity models both in vitro and in vivo. Echocardiography and histological analyses were used to determine the severity of cardiac injury in mice. The myocardial damage markers cTnT, CK-MB, ANP, BNP, and ferroptosis associated indicators Fe2+, MDA, and GPX4 were measured using ELISA, RT-qPCR, and western blot assays. The morphology of mitochondria was investigated with a transmission electron microscope. The levels of mitochondrial membrane potential, mitochondrial ROS, and lipid ROS were detected using JC-1, MitoSOX™, and C11-BODIPY 581/591 probes. Results: Our findings demonstrate that WGX50 protects DOX-induced cardiotoxicity via restraining mitochondrial ROS and ferroptosis. In vivo, WGX50 effectively relieves doxorubicin-induced cardiac dysfunction, cardiac injury, fibrosis, mitochondrial damage, and redox imbalance. In vitro, WGX50 preserves mitochondrial function by reducing the level of mitochondrial membrane potential and increasing mitochondrial ATP production. Furthermore, WGX50 reduces iron accumulation and mitochondrial ROS, increases GPX4 expression, and regulates lipid metabolism to inhibit DOX-induced ferroptosis. Conclusion: Taken together, WGX50 protects DOX-induced cardiotoxicity via mitochondrial ROS and the ferroptosis pathway, which provides novel insights for WGX50 as a promising drug candidate for cardioprotection. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is one of the most lethal diseases due to its high faculty of invasiveness and metastasis. Activity-dependent neuroprotective protein (ADNP) has been regarded as an oncogene in bladder cancer and ovarian cancer. However, the role of ADNP in the regulation of tumor immune response, development, and treatment resistance in HCC remains unknown and is worth exploring. Methods: The correlation between ADNP and prognosis, immune cell infiltration, immune checkpoints, chemokines, tumor mutation burden, microsatellite instability, and genomic mutation of pan-cancer cohorts in The Cancer Genome Atlas was analyzed. ADNP expression in HCC cell lines, HCC and the adjacent normal tissues was measured by western blotting and immunochemistry. Nomogram was constructed to predict the survival of patients with HCC based on the ADNP expression and significant clinical characteristics. The potential biological functions and impacts on radiotherapy of ADNP in HCC cell lines were verified by vitro experiments. Results: ADNP was upregulated in most cancers and patients with elevated ADNP expression were related to poor survival in several types of cancers including HCC. Functional enrichment analysis showed ADNP participated in the pathways correlated with coagulation cascades and DNA double strand break repair. Further, ADNP exhibited a negative correlation with the immune score, stromal score, estimated score, and chemokines, and a positive correlation with cancer-associated fibroblasts, myeloid-derived suppressor cells, neutrophils, regulatory T cells, and endothelial cells. Immunochemistry and western blotting results demonstrated ADNP was up-regulated in HCC. Vitro experiments verified that suppressing the ADNP expression significantly inhibited the proliferation, invasion and migration and elevated the radiosensitivity via decreasing DNA damage repair in HCC. Conclusion: ADNP might play an oncogene and immunosuppression role in tumor immune infiltration and response, thus influencing the prognosis. Its downregulation could attenuate the proliferation, invasion, migration, radioresistance of HCC. Our results indicated the potential of ADNP as a promising biomarker to predict the survival of HCC patients, providing a theoretical basis for novel integrative strategies. [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]

Mn4+-activated perovskite-structured ANaWO2F4 (A = Li, Na, K) red phosphors were successfully prepared by a facile co-precipitation method. By changing the A-site ions, the tolerance factor (t) of host material ANaWO2F4 became adjustable. Red emissions in LiNaWO2F4:Mn4+, Na2WO2F4:Mn4+ and KNaWO2F4:Mn4+ were found to be gradually increased. The relationship between the structure and their photoluminescence properties was discussed. The results suggested that a t-dependent photoluminescence behavior may exist in perovskite-structured phosphors. As the tolerance factor increases, the emission intensity of ANaWO2F4 (A = Li, Na, K) red phosphors increases. This work also provides a reference for the exploration and optimization of Mn4+-activated perovskite-structured red phosphors. [ABSTRACT FROM AUTHOR]

A 657 nm red emission from a novel rare earth free oxide-based CaO–0.5Al2O3–0.5Nb2O5:xMn4+ (0.001 ≤ x ≤ 0.008) phosphors with high water-resistance property were prepared by solid-state reaction method. The composition and structure of the as-prepared phosphors was studied. Under relative ultraviolet (331/365 nm) and blue (465 nm) light excitation, the as-prepared phosphor presents a 657 nm red emission that assigned to the 2Eg → 4A2g transition of Mn4+ ions. The red light source in CaO–0.5Al2O3–0.5Nb2O5:Mn4+ system was discussed, and the water resistance property of the phosphor was also investigated. The as-prepared phosphor presents more proper red emission position than those of similar oxide-based Mn4+-activated phosphors and shows excellent water-resistance property compared with commercial used K2SiF6:Mn4+ phosphor. With the further optimization of its photo-luminescent properties, the as-prepared CaO–0.5Al2O3–0.5Nb2O5:Mn4+ phosphors may find its potential application in the field of white LEDs. [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]

Graphene-based transparent conductive films (TCFs) are promising alternative to indium tin oxide owing to their high transmittance and conductivity. Graphene films were directly deposited on quartz substrates by assisted catalysis of Cu nanoparticles in ambient pressure chemical vapor deposition. Growth conditions, including the concentration of Cu nanoparticles as catalyst, flow rate of CH4, temperature and growth time, were systematically investigated to optimize the quality and performance of graphene TCFs. With the optimized growth conditions, the obtained graphene TCFs exhibit good performance with sheet resistance of 2.48 kΩ sq−1 at transmittance of 82.83%. With this method, graphene TCFs with good performance were obtained without the need of a complex transfer process of graphene, opening a considerable route toward fabricating graphene TCFs on dielectric substrates. [ABSTRACT FROM AUTHOR]

Broadband antireflection coatings (ARCs) attract increasing attentions due to the effective reduction of reflection between the interface of air and substrates over a broad range of wavelengths. Moth-eye-like array ARCs with high antireflection performance have been successfully fabricated via a facile and low-cost sol–gel method using solid silica nanospheres (SSNSs) and hollow silica nanospheres (HSNSs). The composite of SSNSs and HSNSs was closely arranged on the glass substrate to firstly construct the close-packed solid/hollow silica nanospheres (c-S/HSNSs) array, in which HSNSs were used to regulate the refractive index and many triangular grooves among adjacent nanospheres were formed. Then moth-eye-like array structure was obtained by locating the nanospheres on the groove positions in c-S/HSNSs array. The transmittance of glass substrates with moth-eye-like array structure has been increased from 91.0% to 99.0%, with an average solar transmittance of 97.8%. The reflection of glass substrates with moth-eye-like array structure was prominently reduced in wide-angle incidence, and the minimum reflectance changed from 0.17% to 1.34% within 8 to 60°. The moth-eye-like array structure exhibits the high antireflection performance and excellent thermal stability and is promising in photovoltaic modules, optical lenses, and other outdoor applications. Graphical abstract includes the process of preparation (left) and SEM images of morphologies and structures of moth-eye-like array, in which the inset is the crosssectional structure of moth-eye-like array (middle), and the transmittance of moth-eyelike array and c-S/HSNSs array in the range of 350–800 nm (right). Highlights: The close-packed solid/hollow silica nanospheres (c-S/HSNSs) array was constructed by assembling the solid and hollow silica nanospheres on the glass substrate. Moth-eye-like array antireflection coatings based on c-S/HSNSs array have been obtained with excellent performance. The transmittance of glass substrates with the moth-eye-like array structure reaches 99.0%, with an average solar transmittance of 97.8%. The minimum reflection of moth-eye-like array structure changes 0.17% to 1.34% within the scope of 8 to 60°. [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]

Minimization of the lattice thermal conductivity (κL) in thermoelectric (TE) materials is a widely applied strategy to improve the thermoelectric performance of these materials. Dislocations have been demonstrated to be effective in scattering the mid-frequency phonons, which can dramatically reduce the κL in combination with the nanostructures and point defects. Generally, plastic deformation is the most straightforward method to generate dislocations in an alloy. However, most TE materials cannot readily deform plastically due to their brittleness. Herein, we have demonstrated that shock compression is effective in generating high-density dislocations (∼7.9 × 1012 cm−2) in TE materials. Shock compression is an extreme regime of deformation with ultra-high strain rates (＞106 s−1) and high pressures (∼GPa), combined with high temperatures during the process. Using this method, multi-scale hierarchical architectures were fabricated in higher manganese silicides (HMS) with nano-sized grains and high-density dislocations. An ultralow lattice thermal conductivity of 1.5 W m−1 K−1 has been achieved in HMS compounds, and the maximum ZT is increased by 47% to 1.0, which is higher than that of most of the ZT values reported for the HMS compounds. These results demonstrate that dense dislocations not only can lower the κL and improve the ZT of HMS, but can also extend the application of the shock compression method to the design of advanced TE materials. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Enhanced solar light absorption and photocatalytic and photoelectrochemical properties have been achieved in black BaTiO3 with a unique core/shell structure (crystalline BaTiO3@amorphous BaTiO3−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. [ABSTRACT FROM AUTHOR]

The article analyses the potential of ferroelectric (FE) photovoltaics. Topics discussed include technique to modify the physical and chemical properties in material science; relationship between crystal structure and its physical property; and the pressure effects on the photoelectric properties of FE materials along with the x-ray diffraction (XRD).

CuInTe2/graphene composites were fabricated by spark plasma sintering and their thermoelectric properties were investigated. Embedding graphene sheets into CuInTe2 led to decreased thermal conductivity, which can be ascribed to the enhanced phonon scattering by the interface between graphene and the matrix. An improved dimensionless figure of merit (ZT) of 0.40 at 700 K was achieved in a CuInTe2/graphene composite with a mass ratio of 80 : 1. [ABSTRACT FROM AUTHOR]

Cascaded H-bridge power quality improving device (PQID) has garnered extensive attention for its flexible electric energy conversion and fast voltage response. However, the failure rate of PQID is relatively high due to the use of large numbers of power electronic devices. This paper proposes a mechanical-switch based adaptive fault ride-through strategy for improving the operational stability and power supply reliability of PQID. According to the features of the topology and working principle of PQID, this paper summarized the types of internal faults and analyzed the characteristics of different types of faults. Based on the shortcomings of existing mechanical switches as a bypass method, corresponding adaptive fault ride-through strategies are proposed for different types of faults, and a comprehensive simulation test has been carried out. The results show that the proposed strategy can adaptively ride through unit faults and effectively improve the output waveform quality during the ride through time. [ABSTRACT FROM AUTHOR]

Using thermal dissipation and the ICT-2000TE equipment made in Australia, the sap flow of Castanopsis jianfengensis and various environmental factors were measured simultaneously in a mixed tropical montane rainforest at Jianfengling Nature Forest Reserve (18°369′N, 108°52′E, 860 m elevation) during the dry and rainy seasons of 2002. The results show that sap flow velocity of C. jianfengensis exhibited a monopeak pattern on clear days and a multi-peak pattern on cloudy or rainy days. Sap flow velocity had significant positive correlations with solar radiation, air temperature, vapor pressure deficit and wind speed and a negative correlation with air relative humidity. In the dry season, sap flow velocity had a significant positive correlation with soil temperature and poor correlation with soil moisture; it was the opposite in the rainy season, indicating that precipitation clearly affected sap flow. Linear regression models between sap flow and environmental factors were established and were significant at the 0.005 level of probability. The mean transpiration rates of C. jianfengensis were 103.5 and 41.3 kg/d in our single tree and 1.94 and 0.77 mm/d in stand level in the dry and rainy season, respectively. [ABSTRACT FROM AUTHOR]

In this work, a novel red-emitting oxyfluoride phosphor Na2NbOF5:Mn4+ with an ultra-intense zero-phonon line (ZPL) was successfully synthesized by hydrothermal method. The phase composition and luminescent properties of Na2NbOF5:Mn4+ were studied in detail. The photoluminescence excitation spectrum contains two intense excitation bands centered at 369 and 470 nm, which match well with commercial UV and blue light-emitting diode (LED) chips. When excited by 470 nm blue light, Na2NbOF5:Mn4+ exhibits red light emission dominated by ZPL. Notably, the color purity of the Na2NbOF5:Mn4+ red phosphor can reach 99.9%. Meanwhile, the Na2NbOF5:Mn4+ phosphor has a shorter fluorescence decay time than commercial K2SiF6:Mn4+, which is conducive to fast switching of images in display applications. Profiting from the intense ZPL, white light-emitting diode (WLED) with high color rendering index of Ra = 86.2 and low correlated color temperature of Tc = 3133 K is realized using yellow YAG:Ce3+ and red Na2NbOF5:Mn4+ phosphor. The WLED fabricated using CsPbBr3 quantum dots (QDs) and red Na2NbOF5:Mn4+ phosphor shows a wide color gamut of 127.56% NTSC (National Television Standard Committee). The results show that red-emitting Na2NbOF5:Mn4+ phosphor has potential application prospects in WLED lighting and display backlight. [ABSTRACT FROM AUTHOR]