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The hydrolysis of LiAlH4is a feasible path to supply hydrogen at subzero temperatures due to its high hydrolysis reactivity and hydrogen purity. However, the extremely fast hydrolysis reaction of LiAlH4hindered its practical application due to its kinetic instability and safety risks caused by the exothermic effect of the reaction. Herein, hydrophobic graphene nanosheets (GNS) have been coated on the surfaces of LiAlH4particles (LiAlH4@GNS composites) to slow the hydrolysis kinetics of LiAlH4, especially at subzero temperatures. The GNS coating processes have been found to introduce not only GNS coating but also fragmentation of LiAlH4particles. The coating process was found to hinder the hydrolysis reaction of LiAlH4with increasing GNS coating to 3.82 wt %, while the hydrolysis of LiAlH4was found to increase with further GNS coating process due to significant fragmentation effects. The hydrolysis speeds of LiAlH4@GNS (D50= 100 μm, Dδ= 1.30) with GNS coating (∼3.82 wt %) have been demonstrated to be reduced to 70% of that of pristine LiAlH4, where the conversion rates were found to be still higher than 99.0% at −40 to 0 °C. The GNS coating is considered to serve as a barrier to hinder the free diffusion of H2O molecules toward the reaction interface at the initial stage of the reaction, resulting in longer induction periods of the composites than those of pristine LiAlH4. The hydrolysis of LiAlH4@GNS has been demonstrated to follow the shrinking core model controlled by liquid film diffusion, where the GNS coating plays an important role in extending the diffusion distance and reducing the diffusion efficiency of substances within the liquid film layer.

The exfoliation of violet phosphorus into violet phosphorene nanosheets (VPNS) is crucial for various applications. Large quantities of VPNS are typically prepared through solution exfoliation, but prolonged sonication often introduces extra functional groups, influencing their pristine properties. Herein, gas intercalation with thermal-cold cycles has been introduced to enhance VPNS exfoliation and minimize functionalization. The exfoliation of VPNS on the thermal-cold cycle was found to be enhanced by about 50% with helium intercalation. Excellent yield was achieved through thermal (60 °C)-cold cycle treatment in a helium atmosphere. Less functionalized or oxidized VPNS with a larger lateral size (4–7 μm) were obtained compared with those from traditional liquid exfoliation. The optical band gap of the exfoliated VPNS on thermal-cold cycling with helium intercalation was measured by optical transmission spectroscopy to be 2.15 eV, similar to that from mechanically exfoliated ones and slightly smaller than that (2.16 eV) from prolonged sonication. The assistance of gas intercalation for exfoliation was found to be consistent with theoretical prediction by density functional theory, where the penetration barrier of He (pore: 0.54 eV; interlayer: 0.14 eV) was calculated to be much lower than that of Ar (pore: 1.77 eV; interlayer: 10 eV).

Aqueous zinc-ion batteries (AZIBs) are poised to play a pivotal part in meeting the growing demands for energy storage and powering portable electronics for their superior security, affordability, and environmentally friendly characteristics. However, the detrimental side reactions occurring at the zinc anode and the dendrite caused by uneven zinc plating/stripping have greatly compromised the cycling life of AZIBs, thereby impeding their practical prospects. In this study, the interfacial comodulation strategy was employed by combining the “electrostatic shielding” effect of cations with the characteristic adsorption of anions. Two molar ZnSO4served as the matrix, and sodium hydroxyethyl sulfonate (SHES) was selected as a low-cost, nontoxic additive. Experimental results confirm that SHES and zinc anode exhibit robust interactions that lead to the formation of an electrostatic shield and a dynamic adsorption layer at the interface, thereby suppressing hydrogen evolution and corrosion. The combined “electrostatic shielding” effect of sodium ions and the robust characteristic adsorption of hydroxyethyl sulfonate anions serve to guide the directed three-dimensional (3D) diffusion of Zn2+, facilitating rapid, stable, and uniform deposition of zinc. Due to these effects, incorporating 0.2 M SHES as an additive extends the cycle life beyond 3600 h and enables a highly reversible process of deposition and stripping in symmetric cells. Additionally, the Zn–Cu half-cell exhibits reliable cycling for over 1400 cycles, achieving an average Coulombic efficiency of 99.6%. Moreover, the introduction of this additive substantially enhances the performance of Zn-MnO2and Zn-NH4V4O10full cells. This study demonstrates the practical feasibility of achieving anodes with high reversibility in AZIBs through the implementation of a strategy that involves anion adsorption at the interface, which holds paramount significance for the practical application of AZIBs.

• Flexible etherified methylene chains and rigid phenyl structures were introduced into the cross-linking network. • The film coupled hardness with softness improved high-field polarization and high-temperature energy storage efficiency. • The film with side-chain flexible segments showed more outstanding dielectric and thermodynamic properties. The introduction of highly polarized flexible segments into polymer molecular chains is an effective means to improve the dielectric constant and mechanical flexibility of polymers, which is important for improving the energy storage characteristics and applicability for the roll-to-roll process of metallic film capacitors. However, the introduction of flexible segments may adversely affect the heat resistance of polymer materials, which limits their application at high working temperatures. In this work, we have prepared a novel epoxy film with excellent comprehensive properties by introducing rigid phenyl and flexible etherified methylene side chains. For instance, the optimal epoxy film showed an energy storage density of 7.06 J cm–3 and 85% charge-discharge efficiency at room temperature and 420 kV mm–1. At 200 kV mm–1 and 110 °C, a working condition for the application of the electric vehicle, the prepared film still showed an energy storage density of 1.5 J cm–3 and charge-discharge efficiency of 86%, which is 3 times that of BOPP film. This work provides an idea for material designs of high-performance polymer film capacitors. [ABSTRACT FROM AUTHOR]

As one of the most consensus goals around the world, reduction of carbon emissions has attracted huge attention from academic and industry communities for developing renewable energy sources and carbon capture techniques. Nonthermal equilibrium plasma catalysis has been proven to be a very promising way for CO2conversion into high-value-added products; however, the synergistic catalytic mechanism between the plasma and various catalysts remains a challenge. In this work, we designed a reactor of atmospheric pressure glow discharge (APGD) plasma jet coupled with V2O5/TiO2nanocomposite catalysts and studied the influence of V2O5mass fraction, catalyst pretreatment, and reaction plasma parameters on the CO2dissociation performance. Results showed that the designed reactor could introduce high-density plasma to the downstream area and maintain lower gas temperature, allowing the collaboration between APGD and the V2O5/TiO2catalyst. The XRD analysis indicated that the solid solution phase TiVO4could be formed in catalysts by V2O5doping and reach a maximal content at a mass fraction of 30%, which determined the most excellent redox ability of the catalyst. The pretreatment of the as-prepared catalyst by Ar dielectric barrier discharge (DBD) plasma increased the oxygen vacancy density of the catalyst, thereby raising the conversion rate by 18.43%. Moreover, the transition regime between laminar and turbulent states was found to be the optimal configuration for CO2dissociation. The reaction pathway was proposed for CO2dissociation synergistically catalyzed by an APGD plasma jet and V2O5/TiO2. Ultimately, the maximum conversion of 14.88% and energy efficiency of 40.45% were simultaneously achieved, which were superior to the results of most atmospheric pressure plasmas. This work opens an avenue to develop plasma technology for sustainable CO2utilization.

Research on the resistance of materials to ionization radiation and radiation-induced conductivity measurements in X-ray environments has attracted considerable interest in various fields. A system is developed to evaluate the radiation-induced conductivity of alumina samples under steady-state X-ray irradiation. The dose rate and bias electric field ranges are 0.25-1.47 Gy $\cdot $ s-1 and 0.64-3.2 kV $\cdot $ mm-1, respectively. The conductivity rapidly increases from $2.5\times 10^{-16}~\Omega ^{-1} \cdot $ cm-1 to $10^{-14}$ - $10^{-12}~\Omega ^{-1} \cdot $ cm-1 after X-ray irradiation. The steady-state and peak values of the conductivity are positively correlated with the dose rate. When the bias field exceeds 1.28 kV $\cdot $ mm-1, the conductivity gradually decreases and then exponentially increases. The Rose-Fowler-Vaisberg (RFV) model is demonstrated and transformed into ordinary differential equations (ODEs) by discretizing the trap energy levels. The radiation-induced conductivity of alumina is calculated using this model. The parameters are determined under various test conditions. An increase in the electric field accelerates the carrier trapping and recombination processes. Considering the measurement error, the computed findings closely match the test results.

Dielectric film capacitors for high‐temperature energy storage applications have shown great potential in modern electronic and electrical systems, such as aircraft, automotive, oil exploration industry, and so on, in which polymers are the preferred materials for dielectric capacitors. This review tries to summarize the recent progress in the field of energy storage based on heat‐resistant all‐organic polymers from the perspective of their operating temperatures. Based on this, a summary of commonly used and latest research on high‐temperature polymers is conducted, and they are classified into different heat‐resistant insulation grades, consequently providing a new perspective for high‐temperature polymers dielectric research, especially on the selection of them under different occasions. Emphasis is placed on the influencing factors of polymer performance and ways to develop high‐temperature polymers. Especially, properties under high temperature including dielectric constant and loss, glass transition temperature, and energy density are summarized, inspiring researchers devoting further efforts in this area. A future prospect in this field is also discussed.

Taurine (TAU) is introduced as an electrolyte additive to simultaneously regulate the coordination environment and construct an in situ SEI layer for achieving stabilized Zn metal anodes and high-performance full batteries.

The rapid development of renewable energy systems, electric vehicles, and pulsed equipment requires energy storage media to have a high energy storage density and efficiency in a wide temperature range. The state-of-the-art biaxially oriented polypropylene (BOPP) film is insufficient to meet the growing demand for energy storage devices due to its low energy storage density and working temperature, which make it a research hotspot for developing dielectric energy storage materials. In this manuscript, based on the epoxy materials that have been shown as a potential energy storage medium, we aim to reduce the influence of the benzene ring delocalization structure on the energy storage losses and enhance the efficiency by gradually replacing them with cyclohexane structures to adjust the segment unsaturation of epoxy materials. The results show that by partially reducing the unsaturation of the curing agent, the epoxy material achieves an excellent high-temperature energy storage density of 2.21 J/cm3at 150 °C and 300 MV/m while maintaining an extremely high energy storage efficiency of 99.2%. Leakage current density and high-voltage dielectric spectroscopy tests confirm that a moderate reduction of the segment unsaturation of epoxy materials can greatly inhibit polarization loss at high temperatures, which may explain their high energy storage efficiency.

Selective catalytic reduction with ammonia is the mainstream technology of flue gas denitration (de-NOx). The reducibility and acid site are two important factors affecting the de-NOxperformance, and effective regulation between them is the key to obtain a highly efficient de-NOxcatalyst. Herein, a series of Mn–Fe–BTC with different ratios of Mn and Fe are synthesized, among which 2Mn-1Fe-BTC with 2:1 molar ratio of Mn and Fe has excellent low-temperature (LT) de-NOxperformance (above 90% NO conversion between 60 and 270 °C) and good tolerance to H2O and SO2poisoning (88% NO conversion at 150 °C with 100 ppm of SO2and/or 6% H2O). It is revealed that the reducibility properties and acid sites of Mn–Fe–BTC can be flexibly tuned by the ratio of Mn and Fe. The difference in electronegativity between Fe and Mn leads to the redistribution of valence electrons, which enables the controllable reducibility of Mn–Fe–BTC. Furthermore, different amounts of Mn and Fe lead to different electron transport, which determines the type and number of acid sites. The synergistic effect of Mn and Fe endows Mn–Fe–BTC with enhanced surface molecular adsorption capacity and enables the catalyst to selectively chemisorb NH3and NO at different active sites. This research provides guidance for the flexible regulation of reducibility and acid site of LT de-NOxcatalyst.

• Temperature corrections at the typical sintering temperature were addressed properly. • A strong correlation between actual formability of o-MAX phases and the DOS at the Fermi level were found. • Using an updated linear programing optimization algorithm, results of the preparation of o-MAX phase in the existing experiments can be predicted well. • New non-conventional synthetic routes were suggested, expected to improve purity and yield. The reaction thermodynamics for synthesizing the "312" and "413" o-MAX phases using the powder metallurgy are investigated using a linear programing optimization algorithm based on the high-throughput first principles phonon calculations. The validity and reliability of the current methodology are verified by correctly predicting the impurities in four experimentally known o-MAX systems including Cr-Ti-Al-C, Cr-V-Al-C, Mo-Sc-Al-C and Mo-Ti-Al-C. The formability of each investigated o-MAX phase is evaluated by means of formation enthalpy and formation Gibbs free energy in a temperature range from 0 K to 1700 K. It is revealed that the thermodynamic stability of the "413" o-MAX structure is no better than that of the "312" phase. The formability of "413" o-MAX is also reduced at high sintering temperature, compared to that of "312" phase. The optimal synthetic routes are predicted for all thermodynamically stable "312" and "413" o-MAX phases. It is found that most o-MAX phases considered could be prepared as the single phase using the non-conventional synthetic routes from the aspect of reaction thermodynamics. Few of them including Cr 2 TaAlC 2 , Nb 2 HfAlC 2 , Nb 2 TaAlC 2 , Nb 2 Hf 2 AlC 3 , Nb 2 Ta 2 AlC 3 , Mo 2 V 2 AlC 3 and Mo 2 Ta 2 AlC 3 are predicted to be either destabilized at high temperature or overwhelmed by the most competing side reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

X-ray irradiation on dielectric materials will affect their electrical properties, reducing the service life of the equipment. Therefore, calculating and measuring the radiation-induced conductivity is of tremendous significance in studying the radiation effects of dielectric materials. For the research requirements of detector calibration and numerical calculation of radiation-induced conductivity, the generation method of quasi-monochromatic X-ray is studied. The geometric model is established, and the Monte Carlo numerical simulations of the emitted energy spectrum and the photon numbers are carried out. A steady-state quasi-monochromatic X-ray conductivity measurement system was built to test polyimide materials. Experiments show that under a strong electric field and quasi-monochromatic X-ray, the volume conductivity of the sample can rise to 10−16– $10^{-15}\,\,\Omega ^{-1} \cdot \text { cm}^{-1}$ . The radiation-induced conductivity is in the order of $10^{-16}\,\,\Omega ^{-1} \cdot \text { cm}^{-1}$ and increases with the X-ray intensity. The Rose-Fowler-Vaisberg (RFV) model is discretized for MATLAB numerical calculation. The radiation-induced conductivity of polyimide material is calculated based on the model under specified X-ray energy and X-ray tube current. The calculated results are consistent with the experimental results using the given parameters. The radiation-induced conductivity increases linearly with the increase of X-ray intensity.

Power systems and electrical grids are critical for the development of renewable energy. Electrical treeing is one of the major factors that lead to electrical damage in insulating dielectrics and decline in the reliability of power equipment and ultimately results in catastrophic failure. Here, we demonstrate that bulk epoxy damaged by electrical treeing is able to efficiently heal repeatedly to recover its original robust performance. The classical dilemma between the insulating properties and electrical-damage healability is overcome by dynamic fluorinated carbamate bonds. Moreover, the dynamic bond enables the epoxy to have admirable degradability, which is demonstrated to be used as an attractive green degradable insulation coating. When used as a matrix for fiber-reinforced composites, the reclaimed glass fibers after decomposing the epoxy maintained their original morphology and functionality. This design provides a novel approach for developing smart and green dielectrics to enhance the reliability, sustainability and lifespan of power equipment and electronics.

Graphene oxide (GO) has been unveiled to exhibit high proton conductivity in a humidified or aqueous environment, making it a promising candidate to construct proton conduction nanochannels. In this work, we systematically investigate how the confinement effect and surface chemistry influence the proton transportation behavior in graphene-based nanochannels via extensive ReaxFF MD simulations. Graphene (GE), graphane (GA), and hydroxygraphane (HG) sheets were employed to mimic the graphitic and functionalized region of GO and construct nanochannels with different interlayer distances. We find that confined water molecules are stratified and their orientation is influenced by the surface chemistry, thus impacting the distribution of protons. Surface chemistry makes the compression of the hydrogen-bond network induced by the confinement effect more variable. The hydrogen-bond network between GE slabs is crushed by extreme confinement and ultrafast proton transportation behavior mainly achieved via vehicle mechanism. Meanwhile, the hydrogen-bond network and solvation structure can be kept more complete with the existence of functional groups. The hydrogen bonds formed with surface functional groups impede the transportation of water molecules but allow more Grotthuss hopping of protons to different extents. Our work clarified the proton transportation mechanism in graphene-based nanochannels with different interlayer distances and surface chemistry and can guide the future design of proton conduction devices such as proton exchange membranes.

Herein, a new photocatalyst PdS@UiOS@CZS is successfully synthesized, where thiol-functionalized UiO-66 (UiOS), a metal–organic framework (MOF) material, is used as a host to encapsulate PdS quantum dots (QDs) in its cages, and Cd0.5Zn0.5S (CZS) solid solution nanoparticles (NPs) are anchored on its outer surface. The resultant PdS@UiOS@CZS with an optimal ratio between components displays an excellent photocatalytic H2evolution rate of 46.1 mmol h–1g–1under visible light irradiation (420∼780 nm), which is 512.0, 9.2, and 5.9 times that of pure UiOS, CZS, and UiOS@CZS, respectively. The reason for the significantly enhanced performance is that the encapsulated PdS QDs strongly attract the photogenerated holes into the pores of UiOS, while the photogenerated electrons are effectively migrated to CZS due to the heterojunction effect, thereby effectively suppressing the recombination of charge carriers for further high-efficiency hydrogen production. This work provides an idea for developing efficient photocatalysts induced by hole attraction.

Although substantial efforts have been made, controllable synthesis of p-type WS2remains a challenge. In this work, we employ NaCl as a seeding promoter to realize vapor–liquid–solid (VLS) growth of p-type WS2. Morphological evolution, including a one-dimensional (1D) nanowire to two-dimensional (2D) planar domain and 2D shape transition of WS2domains, can be well-controlled by the growth temperature and sulfur introduction time. A high growth temperature is required to enable planar growth of 2D WS2, and a sulfur-rich environment is found to facilitate the growth of high-quality WS2. Raman and photoluminescence (PL) mappings demonstrate uniform crystallinity and high quantum efficiency of VLS-grown WS2. Moreover, monolayer WS2-based field-effect transistors (FETs) are fabricated, showing p-type conducting behavior, which is different from previous reported n-type FETs from WS2grown by other methods. First-principles calculations show that the p-type behavior originates from the substitution of Na at the W site, which will form an additional acceptor level above the valence band maximum (VBM). This facile VLS growth method opens the avenue to realize the p–n WS2homojunctions and p/n-WS2-based heterojunctions for monolayer wearable electronic, photonic, optoelectronic, and biosensing devices and should also be a great benefit to the development of 2D complementary metal–oxide–semiconductor (CMOS) circuit applications.

Montmorillonite (MMT) is an abundant silicate mineral with ultrahigh stability. The exfoliation of stacked MMT into high-aspect-ratio nanosheets is of crucial importance for various applications such as toxic gas suppression, barrier property enhancement, flame retardancy, and ion conduction. In this work, we develop a new heating/rehydrating and gas-pushing method that can successfully exfoliate MMT into nanosheets with aspect ratios (600–5000) far higher than the currently reported values (1–120). The MMT first goes through a “starvation pretreatment” under different heating temperatures to improve its hydrophilicity and is then rehydrated in a hydrogen peroxide solution. The hydrogen peroxide in the MMT interlayer space can decompose into water and oxygen bubbles, thus finally leading to the exfoliation via gas-pushing while preserving the large lateral size (mainly in the range of 1–6 μm) of the nanosheets. By changing the pretreatment temperature and pH value of the hydrogen peroxide solution, the exfoliation performance can be tuned. This simple and low-cost exfoliation method is promising to achieve the mass production of MMT nanosheets with a high aspect ratio and may promote its application in various fields such as energy conversion, drug delivery, and photocatalysis.

Employing first-principles calculations, the energy storage properties and ion diffusion dynamics of Li+, Na+, K+, Mg2+, Ca2+, Zn2+, and Al3+on bare (Mo2/3Sc1/3)2C and surface-functionalized (Mo2/3Sc1/3)2CT2(T = −O, −OH, and −F) i-MXenes are predicted. The investigated i-MXenes show weak adsorption ability to the Zn2+ion regardless of the surface terminations, excluding their use as anodes for Zn ion batteries. The first-principles molecular dynamics simulations indicate that the adsorption of alkaline (earth) metal ions and Al3+on (Mo2/3Sc1/3)2C(OH)2and (Mo2/3Sc1/3)2CF2causes the surface reaction between metal ions and surface terminations, leading to the formation of metal hydride or fluorite overlayers covering the underneath remaining i-MXenes. We find that the bare (Mo2/3Sc1/3)2C and (Mo2/3Sc1/3)2CO2are suitable candidates for use as anodes for alkaline (earth) metal and Al ion batteries. Specifically, both (Mo2/3Sc1/3)2C and (Mo2/3Sc1/3)2CO2i-MXenes show good ion storage capacities, ideal open circuit voltages, and fast ion diffusion dynamics for alkaline (earth) metal ions. Notably, the predicted theoretical capacities of (Mo2/3Sc1/3)2C ((Mo2/3Sc1/3)2CO2) for Li+, Mg2+, and Al3+are 291 mAh g–1(254 mAh g–1), 490 mAh g–1(436 mAh g–1), and 886 mAh g–1(640 mAh g–1), respectively. In addition, the calculated open circuit voltage profiles of Li+, Mg2+, and Al3+exhibit the small on-set voltage and the board plateau region. The climbing image-nudged elastic band predicts that the diffusion energies of Li+, Na+, K+, and Ca2+ions on bare (Mo2/3Sc1/3)2C are extremely small (<0.05 eV), and the O-terminated surface show higher diffusion energies for various metal ions. Overall, (Mo2/3Sc1/3)2C and (Mo2/3Sc1/3)2CO2are good electrode materials for fast charging alkaline (earth) metal ion batteries and supercapacitors.

Phosphorene is another layered elemental structure after graphene. The mechanical property is an important character for two-dimensional (2D) structures. The 2D Young’s modulus (E2D), representing the deformation resistance of 2D nanostructures, has been investigated for the black phosphorene (BP) nanoflakes with thicknesses of 6–22 nm (11–43 layers) by an atomic force microscope nanoindentation method. The nanoeffects have also been found to significantly affect the E2Dof BP nanoflakes. The BP E2Dincreases as the layers decreasing. The E2D-layer model for BP nanoflakes has been deduced to follow E2D(n) = 53.31(1 + 3.30e–0.13n), where the E2Dof monolayer BP was deduced to be 214 ± 11 N/m. The E2Danalysis model and E2D-layer model have been well used to deduce the E2Dof BP nanoflakes.

Recently, one η1-coordinated complex of endohedral metallofullerene (EMF) Y@C2v(9)-C82[Re(CO)5] has been synthesized and characterized with a highly efficient radical-coupling methodology by performing a photochemical reaction between Y@C2v(9)-C82and [Re(CO)5]2complexes. Theoretical investigations with the density functional theory reveal that this complex is stabilized by an ionic C–Re bond. The reactions of M@C2v(9)-C82(M = Sc, Y, La) with [Re(CO)5]2suggest that the reaction energies differ little because of similar single occupied molecular orbitals (SOMOs) of M@C2v(9)-C82. In the reactions of Y@C2v(9)-C82with various transition-metal complexes [M′Ln]2(M′ = Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir), the C–M′ bonds with Mn, Tc, Re, Fe, Ru, and Os can stably exist, whereas those with Co, Rh, and Ir are unstable. Further analyses disclose that, in each element group, the stability of the C–M′ bond is mainly determined by the bond energy of the M′–M′ bond, which is related to the dσorbital of the M′Lnspecies. Moreover, the very-low-energy dσorbitals and large geometrical distortions of M′(CO)4(M′ = Co, Rh, Ir) lead to poor stabilities of the C–M′ (M′ = Co, Rh, Ir) bonds. As comparison, the reactions of Y@Cs(6)-C82and La@C72have been investigated. The Y@Cs(6)-C82structure is more reactive toward the [M′Ln]2complexes than Y@C2v(9)-C82thanks to a lower SOMO of Y@Cs(6)-C82than that of Y@C2v(9)-C82, which derives from position change of the Y atom in Cs(6)-C82during the reactions. However, the formation of [Y@Cs(6)-C82]2suppresses the formation of several C–M′ bonds. The reactivity of La@C72is weak due to a high LUMO+1 of C72, which leads to a high SOMO of La@C72. We believe that this theoretical study provides primary principles of radical-coupling reactions of EMFs and will be valuable for future research of organometallic complexes of fullerene.

[Display omitted] • LiCa 3 Mg(VO 4) 3 with oxygen vacancies were rationally adjusted under oxygen flow with different time for the first time. • The as-obtained the LCMV-O 2 -1H exhibited the highest PLQY of 69.34 % and the longest decay time of 16.107 μs. • 1 h oxygen treatment repaired oxygen vacancies while over-treatment introduced more surface defects. • The surface defects led to the absorption of oxygen and water in air, resulting in the decreased PLQY. As a kind of white light emitting diode (w-LED) with many advantages, rare-earth-free vanadate phosphor has attracted more and more attention. The oxygen vacancies and other surface defects in vanadate oxide have obvious effects on its structure and properties. In order to reveal the specific effects, we heat-treat the original LiCa 3 Mg(VO 4) 3 (LCMV) in an oxygen flow with different time to decrease oxygen vacancies, and find that the lattice distortion of [VO 4 ] tetrahedron caused by oxygen vacancy is effectively reduced. Meanwhile, the crystallinity of the treated samples increases, the surface defects decreases, and the fluorescence intensity increases. The variation of photoluminescence quantum yield (PLQY) with oxygen treatment time is as follows: the enhancement effect firstly reaches the strongest (69.34 %) within one hour, then begins to decline after two hours, and finally reaches the platform after three hours and remains basically unchanged. The reason for the enhancement of PLQY is the decrease of oxygen vacancy after one-hour treatment, and the reason for the decrease of PLQY after a further increased treatment time is that the absorption of oxygen and water in air caused by excessive surface defects introduced by oxygen treatment. [ABSTRACT FROM AUTHOR]

Perovskites are promising alternative materials for conventional Ni-based cermet anodes, benefitting from their mixed ionic and electronic conductivity properties and good structure stability. However, they generally show a commonplace electrochemical catalytic activity. Here, a novel anode material La0.52Sr0.28Ti0.8Co0.1Fe0.1O3−δ(LSTCF) is successfully synthesized, and we report that the electrochemical performance of LSTCF can be commendably tuned by gas treatment, deriving from the exsolution of the impressively well-distributed Co–Fe alloy nanocatalyst with splendid catalytic activity for hydrogen electrochemical oxidation. At 900 °C, a power density value of 897 mW cm–2is achieved by the treated LSTCF anode when using hydrogen as fuel, which is almost three times higher than that of the fresh anode. Moreover, we show that the nanoparticle-modified LSTCF perovskite also exhibits fascinating electrochemical catalytic activity at low temperatures.

Study design Clinical study.Objective Our work was aimed at exploring the expression and clinical significance of microRNA-138-5p (miR-138-5p) and Transforming Growth Factor-beta 3 (TGF-β3) in peripheral blood of patients with ankylosing spondylitis (AS).Methods Forty-seven patients with AS were selected as the AS group, and the staging of the enrolled AS patients was based on the BASDAI score: <4 points were classified as the stable stage (stable group) and ≥4 points were classified as the active stage (active group). Forty-seven cases were selected from the same period of healthy physical examination in our hospital as the control group. miR-138-5p and TGF-β3 levels and disease activity factors in peripheral blood were measured in all patients.Results Compared to healthy subjects, reduced miR-138-5p levels and increased TGF-β3 levels were found in AS patient. Even more, level of miR-138-5p was decreased and level of TGF-β3 was found to be increased in active disease stage of AS in comparison to inactive disease. Correlation analysis disclosed that miR-138-5p expression in peripheral blood of AS patients was negatively correlated with TGF-β3, HLA-B27, ESR, CRP, and BASDAI; serum TGF-β3 was positively correlated with HLA-B27, ESR, CRP, and BASDAI. The ROC curve analysis disclosed that miR-138-5p and TGF-β3 had certain diagnostic value for AS, and the combined detection could improve the clinical diagnostic capability of this disease.Conclusion miR-138-5p and TGF-β3 in peripheral blood of AS patients are potential biological markers for the diagnosis of AS and are expected to be new clinical diagnostic indicators.