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In situ characterization, as a real-time monitoring method, is used to address various issues in Li metal anodes.The application of in situ characterization helps to promote the further commercialization of Li-metal batteries.

Salinity is a major abiotic stress that restricts cotton growth and affects fiber yield and quality. Although studies on salt tolerance have achieved great progress in cotton since the completion of cotton genome sequencing, knowledge about how cotton copes with salt stress is still scant. S-adenosylmethionine (SAM) plays important roles in many organelles with the help of the SAM transporter, and it is also a synthetic precursor for substances such as ethylene (ET), polyamines (PAs), betaine, and lignin, which often accumulate in plants in response to stresses. This review focused on the biosynthesis and signal transduction pathways of ET and PAs. The current progress of ET and PAs in regulating plant growth and development under salt stress has been summarized. Moreover, we verified the function of a cotton SAM transporter and suggested that it can regulate salt stress response in cotton. At last, an improved regulatory pathway of ET and PAs under salt stress in cotton is proposed for the breeding of salt-tolerant varieties.

The Sr4Al14O25:Eu2+/3+ phosphor was synthesized in air via conventional high-temperature solid-state reaction. Eu3+ in the host lattice was partially self-reduced to Eu2+, and the characteristic excitation and emission of Eu2+ and Eu3+ were detected simultaneously. Due to the different temperature quenching mechanisms of Eu2+ and Eu3+, the luminescent performance and fluorescence intensity ratio of Eu2+/3+ co-activated phosphor presented great temperature dependence. With the increase of the operating temperature, the emitting color of the phosphor can be tuned from bluish green to white. The maximum absolute and relative temperature sensitivity of Sr4Al14O25:Eu2+/3+ phosphor can be as high as 0.015 K−1 at 525 K and 1.1% K−1 at 375 K, respectively. In addition, the decoupled emission peaks of Eu2+ and Eu3+ provide strong signal discrimination for temperature measurement. All the results indicate that the Sr4Al14O25:Eu2+/3+ phosphor possesses excellent temperature-sensing characteristic and can be a promising candidate for ratiometric optical thermometry applications.

Manganese oxide (MnO) is prospective as anode material for lithium-ion batteries (LIBs) due to its low insertion voltage and high reversible capacity. Here, urchin-like MnO microspheres with carbon coating (u-MnO/C) are synthesized through hydrothermal method, and its lithium storage performance is investigated. The unique urchin-like structures of u-MnO/C endow it high surface area which provides sufficient contact with electrolyte. The carbon coating can effectively suffer volume change of u-MnO during charge/discharge process. Meanwhile, the carbon coating can effectively improve the conductivity of u-MnO-based anode. Due to the above features, u-MnO/C delivers high initial capacity of 845 mAh g−1, and an obvious activation process is observed at the beginning of the cycles thanks to the abundant invasion of the electrolyte into u-MnO/C. The large capacity of 723 mAh g-1 can still be achieved after 80 cycles. This work provides a promising guide for designing high-performance LIBs electrode materials.

In this study, we focus on important global issue containing both environmental pollution control and energy saving. High density polyethylene (HDPE) is utilized as supporting material to load paraffin, while Al2O3 nano-powder is added into composite behaving as thermal conductivity enhancement to form composite phase change materials (paraffin-Al2O3/HDPE composite PCMs). By the adsorption test and differential scanning calomeritry (DSC) curves, the loading ratio of paraffin in paraffin/HDPE composite is 60%, via taking phase change enthalpy and thermal conductivity into integrated consideration, the adding ratio of Al2O3 is 3% in paraffin-Al2O3/HDPE composite. And CMT4304 universal tester results manifest paraffin-Al2O3/HDPE composites have high compressive strength. For paraffin-Al2O3/HDPE composite with 3 mass% Al2O3, Fourier transformation infrared (FT-IR) result indicates no chemical interaction among raw materials but physical combination. DSC results identify composite PCM happens solid–solid phase transition at 33.3 oC with enthalpy value of 10.7 J g−1 and melts at 48.8 oC with enthalpy value of 95.1 J g−1, and thermal cycling measurements demonstrate the form-stable composite PCM with adequate stability after 300 times melting/freezing cycles. Furthermore, the thermal conductivity of paraffin/HDPE composite is enhanced by 119.4% to attain 0.419 Wm−1 K−1 after addition of Al2O3. To sum up, form-stable and tough paraffin-Al2O3/HDPE composite PCMs look promising for application in building field as solar energy utilization materials.

The limited resources and uneven distribution of lithium stimulate strong motivation to develop new rechargeable batteries that use alternative charge carriers. Potassium-ion batteries (PIBs) are at the top of the list of alternatives because of the abundant raw materials and relatively high energy density, fast ion transport kinetics in the electrolyte, and low cost. However, several challenges still hinder the development of PIBs, such as low reversible capacity, poor rate performance, and inferior cycling stability. Research on the cathode is currently focused on developing materials with high energy density and cycling stability, mainly including layered transition metal oxides, polyanion compounds, organic compounds, etc. Anodes based on intercalation reactions, conversion reactions, and alloying with potassium are currently under development, and promising results have been published. This review comprehensively summarizes the research effort to date on the electrode material optimization (e.g., crystals, morphology, reaction mechanisms, and interface control), the synthesis methods, and the full cell fabrication for PIBs to enhance the electrochemical potassium storage and provide a platform for further development in this battery system. This journal is

Metal selenide has attracted much attention for use in rechargeable batteries due to its excellent conductivity and considerable capacity. However, it is still necessary to achieve a long cycle life and excellent Na+ storage performance to enable its practical application. Volume expansion and poor stability of selenide during operation also hinder its industrial applications. As metal-organic frameworks and aerogels possess porous structures, carbon materials derived from them can effectively reduce the volume expansion of selenide, resulting in improving cycling stability and enhancing Na+ storage. In this work, CoSe/C@C composites with a hierarchical structure were successfully prepared by freeze-drying and in situ selenization as anode materials. The CoSe/C@C composites exhibited superior cycling stability (a capacity of 332.3 mA h g-1) and capacity retention (63.1% compared to the second cycle) at 200 mA g-1, after 500 cycles. CoSe/C@C also exhibited a high rate performance of 403.4 mA h g-1 at 2 A g-1. Moreover, thanks to the high capacitance contribution and some redox reactions during cycling, the CoSe/C@C electrode possesses outstanding rate capability.

The development of flexible smart phase change fibers has been limited because of the low production rate and safety concerns of electrospinning. Therefore, a novel centrifugal spinning technology,...

Mn4+-activated fluorides have become a research hotspot in the community of inorganic red phosphors owing to their fascinating luminescent properties. However, the poor water resistance of these materials severely hinders their application in the fields of wide color gamut (CG) backlight display and warm white solid-state lighting. Herein, we propose a green, facile method, i.e., treatment with oxalic acid (H2C2O4) solution, for constructing a homogeneous Mn4+-rare surface shell layer to improve the water-resistant property of K2GeF6:Mn4+ (KGF) red phosphor. The moisture-resistant property of the treated KGF (T-KGF) phosphor was significantly enhanced; however, no significant change was observed in its luminescent properties. Furthermore, the reasons for the excellent water resistance of T-KGF were investigated in detail, and the formation mechanism of Mn4+-rare surface shell layer was proposed simultaneously. Results indicated that the Mn4+-rare surface shell layer was in situ deposited on the T-KGF core during the solid-liquid equilibrium process. Upon employing the as-treated T-KGF red phosphor, high-performance white light-emitting diode (WLED) with Ra of 86.3, correlated color temperature (CCT) of 3824 K, high luminous efficiency (LE) of 152.37 lm/W for WLED2 and an ultrahigh CG (120.1% NTSC standard and 89.7% Rec. 2020 standard) and high LE of 103.12 lm/W for WLED3 were achieved. These results demonstrate that the proposed facile strategy may open a new opportunity to promote the commercialization of Mn4+-activated fluoride phosphors.

Because of their high capacity and low potential, lithium metal anodes are considered to be promising candidates for next generation electrode materials. However, the safety concerns and limited cycling life associated with uncontrollable dendrite growth hamper practical applications. In this work, the acidified cellulose ester, which is a mixed fiber microporous membrane film, was used as a novel electrolyte additive that effectively improves the cycle stability of the lithium metal anode and inhibits dendrite growth. The focus of this paper is on inhibiting the formation and growth of lithium dendrites. The coulombic efficiency of a Li|Cu battery with this acidified cellulose ester additive remains stable at 99% after 500 cycles under a current density of 1 mA/cm2. Symmetric batteries also remain stable after 500 cycles (1000 h) under a current density of 1 mA/cm2. These superior properties can be ascribed to the induced nucleation and the uniform distribution of lithium ion flux. This study uncovers an approach for effectively enabling stable cycling of dendrite-free lithium metal anodes.

Graphite foams were prepared using foaming method and template method with nature flake graphite powder as main raw materials, sucrose as a foaming agent or binder, as well sodium chloride as a template. The compositions, microstructure, thermal properties and mechanical performance of the fabricated graphite foams were investigated by X-ray fluorescence spectrometer, scanning electron microscope, laser thermal conductivity meter, and electronic universal testing machine, respectively. The results show that water in binder played an important role in forming process of graphite foams. Graphite foams with controllable pore structure can be obtained by template method. The porosity of graphite foams increased with increasing the concentration of templating agent. With a fixed concentration of the templating agent the thermal diffusivity of the foams deceased with increasing the concentration of binder. Moreover, the obtained graphite foams has a minimum density of 288 kg/m3, a maximum porosity of 78% and a maximum thermal diffusivity of 7.14 × 10−6 m2/s. Two binding models of graphite foams prepared using template method has been proposed in the first time. This work provided an optimized processing for graphite foams with simple preparation, low-cost recyclable raw materials, and a promising thermal management material for many applications.

In this work, we investigated how the substitution of Nb in the well-established Li7La3Zr2O12 (LLZO) affects its structure and electrochemical performance. The Nb-doped solid-state electrolytes Li7-xLa3Zr2-xNbxO12 (x = 0, 0.25, 0.5, 0.75 and 1.0) were synthesized in zirconia crucibles instead of alumina, in order to eliminate the adverse influence of alumina. The stabilization of the cubic structure of the lithium garnet has been confirmed. The sintered density and ionic conductivity of the Nb-doped LLZO garnets (designated LLZNO) first increase until the Nb content reaches x = 0.5, beyond which these values decrease. We also found that exposing the synthesized garnets in humid air deteriorates ionic conductivity. The degrading mechanism relating to the exposure of the garnets is also discussed. In addition, the cycling stability of the LLZNO (x = 0.5) was assessed by cyclic voltammetry (CV) and charge/discharge cycling testing.

Novel and stringent automotive exhaust gas emissions standards are urgently needed to counter the problems posed by the worsening global climate and environment. However, the traditional cordierite-based honeycomb ceramics substrates with ultimate pore density have seriously restricted the establishment of new emission standards. Herein, we introduce a novel robust substrate with tailored volume-specific surface area and low heat capacity. This substrate employs the synergy of high-strength ceramic fibers and ultrathin TiO

In this work, pressureless sintering (PLS) method was used to prepare Li 7 La 3 Zr 2 O 12 based Al-free garnet electrolytes with the substitution of tantalum (Ta). A series of Ta-doped lithium garnets Li 7- x La 3 Zr 2- x Ta x O 12 (LLZTO, x = 0, 0.25, 0.5, 0.75 and 1.0) were prepared, and the effect of Ta on the structure, densification and ionic conductivity was investigated. Both relative density and ionic conductivity of the LLZTO pellets are dependent on the content of Ta substitution, with the maximum values being reached at x = 0.5. We also studied the stability and degradation mechanism of lithium garnets (Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 ) in humid air with relative humidity of above 70%. It is revealed that after exposure in the humid air for 4 weeks, a layer of LiOH∙H 2 O was observed on the grain boundaries, which lowered its ionic conductivity considerably. In comparison, the pellet stored in a desiccator had clear surface with negligible change in the ionic conductivity.

Ferrihydrite/manganese dioxide composites (FH-M) were synthesized from ferrihydrite (FH) and manganese compounds by ex situ synthesis and characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy in the present work. The influences of experimental parameters such as the solution pH value and initial concentration of adsorbate on the adsorption uptake of Cd(II)/As(V) was systematically investigated. The adsorption kinetics was analyzed by fitting quasi-first-order and quasi-second-order kinetic equations. The results showed that with increase in the pH value, the adsorption rate of Cd(II) is increased, while that of As(V) is increased first and then decreased. For the kinetic adsorption process, the adsorption performance of FH-M to As(V) was better than that to Cd(II). The quasi-second-order kinetic equation and Freundlich equation were more suitable to describe the adsorption of Cd(II)/As(V). The ligand exchange of Cd(II)/As(V) with the -OH in the composites was confirmed by analyzing the characterization results of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The high adsorption ability of the FH-M makes it a potentially attractive adsorbent for the removal to Cd(II) and As(V) with a good application prospect.

Control of Eu valence is one of the main issues to obtain mixed−valent Eu2+/3+ co−doped phosphor with flexible−tunable emission spectra. In this study, for the first time, we report a simple single cation substitution strategy for controlling Eu valence. The structure of Sr1−xBaxAl2Si2O8 host was tailored by Ba2+ substitution for Sr2+ ions. The lattice parameters show a linear evolution with increase in Ba2+ amount. Correspondingly, the Eu3+ emission intensity also increases over Ba2+ amount. The spectral variation was considered to be attributed to the suppression of Eu3+ reduction by the lattice stress, which is introduced by ion substitution. Finally, valence control of Eu and spectral tuning of Eu3+/2+ co−doped Sr1−xBaxAl2Si2O8 phosphor were realized by the proposed strategy. This study will open a novel avenue for Eu valence control and spectral tuning of mixed–valent Eu doped phosphors.

Bismuth (Bi)-based photocatalytic materials are widely used in the field of photocatalytic degradation of wastewater. In this study, β-Bi2O3/BiOBr heterojunction photocatalysts were prepared by an in situ chemical transformation method. BiOBr molecules are arrayed to cross each other to form a pore around β-Bi2O3. The prepared photocatalyst had a large specific surface area and excellent adsorption and photocatalytic properties. The β-Bi2O3/BiOBr with a molecular ratio of 11.1% had the highest catalytic activity. The result of a degradation experiment, performed with Rhodamine B (RhB) as the target pollutant, revealed that the degradation rate reached 99.85% after 25 min under visible light irradiation. The pore structure can adsorb contaminants and the heterojunction facilitates the separation of photogenerated electron–hole pairs to enhance the photocatalytic properties. The high adsorption performance and heterojunction achieved higher photocatalytic efficiency. This semiconductor photocatalyst with high adsorption performance provides a new approach to control water pollution.

In this study, form-stable tetradecanol (TD)/expanded perlite (EP) composites by adding Cu powder (CuP) and carbon fiber (CF) to enhance thermal conductivities have been prepared via vacuum impregnation method. The thermal conductivity enhancer (TCE) is introduced by two methods of mixing TCE with phase change materials (PCMs) and implanting TCE into matrix materials. The result demonstrates the former is better than the latter in aspects of thermal property, thermal conductivity and controllability, moreover, adding ratio of TCEs gather in more appropriate interval from 2.5% to 3% suitable for the former. For CPCMs, FT-IR results indicate it is no chemical interaction among raw materials but physical combination via two methods. CPCMs prepared by the method of mixing TCE with PCMs have better phase change latent heat and thermal stability by DSC and TGA, while thermal cycling measurements show that form-stable composite PCMs have adequate stability even after being subjected to 200 melting/freezing cycles. Therefore, the method of mixing TCE with PCMs has better thermal property and controllability than that of implanting TCE into matrix materials and the prepared CPCM has great application prospect in solar energy utilization, building material, indoor cooling instrument and so on for thermal energy storage.

In this study, novel form-stable composite phase change materials (FS-CPCMs) were prepared by the incorporation of a eutectic mixture of lauric-stearic acid (LA-SA) into carbonization corn cob (CNCC). CNCC served as a good supporting material that not only prevented the leakage of LA-SA but also enhanced its thermal conductivity. Scanning electron microscopy results demonstrated that CNCC exhibits a highly porous structure comprising rough micropores. The retention of 77.9 wt% of LA-SA in CNCC without leakage was observed. Differential scanning calorimetry results revealed that LA-SA/CNCC FS-CPCMs melt at 35.1 °C with a latent heat of 148.3 J/g and solidify at 29.7 °C with a latent heat of 144.2 J/g. The thermal conductivity of LA-SA/CNCC FS-CPCMs was approximately 87.5% greater than that of LA-SA. Thermogravimetric analysis and 200-cycle experiments indicated that the LA-SA/CNCC FS-CPCMs exhibit excellent thermal stability and form-stable performance. Therefore, the as-prepared LA-SA/CNCC FS-CPCMs demonstrate promise for building energy-efficiency applications.

Phase change materials (PCMs) require an excellent matrix support material such as porous carbon materials. Orange peel, a discarded, readily available raw material, could potentially be used to pr...

Crystal structure tailoring is a commonly used method for tuning the luminescence of phosphors. This study mainly aims at luminescent spectra tuning of Sr1−xBaxAl2Si2O8:Eu2+ phosphors by substitution of Ba for Sr ions. The phase composition was characterized by X-ray powder diffraction and the crystal structure was determined by using the Rietveld refinement method. The excitation and emission spectra, diffuse reflectance spectra, and thermal quenching were also investigated in detail. The results show that Sr1−xBaxAl2Si2O8:Eu2+ phosphors can form a series of continuous solid solutions in the range from 0 to 0.75. With the increase in x value, the emission spectra show an obvious redshift from 415 to 450 nm. The emission redshift plays an important role in enabling Sr1−xBaxAl2Si2O8:Eu2+ to be used as a standard blue phosphor for application in white-light-emitting diodes.