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Recently, blue-emitting phosphors have attracted great interest due to their application in full-spectrum white light illumination.

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.

Using the solid-state method, a novel optical thermometer, RbCaLa1-x(VO4)2:xEu3+ phosphor, was synthesized. Using X-ray diffraction, the phase of the RbCaLa1-x(VO4)2:xEu3+ was confirmed. The microstructure was then observed in the SEM pattern. To estimate the temperature, the fluorescence intensity ratio (FIR) method was used. To explain the temperature-sensing properties, the absolute (Sa) and relative (Sr) sensitivities were calculated. The maximum Sa and Sr values were then determined as 2.215% and 1.125% at 473 and 423 K, respectively. After multiple heating and cooling processes, the FIR value corresponding to each temperature stabilized. This indicated the reliability of the FIR fitting formula. Subsequently, to examine the formula's accuracy, multiple temperature points ranging from 298 to 473 K were selected. The results demonstrated that the measurement error could be controlled in ±1.1 K. The difference was considerably lesser in the high-temperature region (400–430 K), and the error was in ±0.21 K. Under UV light, the colors of the RbCaLa0.82(VO4)2:0.18Eu3+ phosphor and RbCaLa(VO4)2 matrix were somewhat different, and both considerably changed with temperature. All results showed that the Eu3+-doped RbCaLa(VO4)2 phosphor is a good candidate material as an optical temperature sensor and anti-counterfeiting coating.

Recently, blue-emitting phosphors have attracted great interest due to their application in full-spectrum white light illumination. In this paper, a novel blue-emitting MgAl

Two cyan-emitting phosphors with different bandwidths were successfully synthesized through the high-temperature solid-state method in a reducing atmosphere. The crystal structures, morphologies, and luminescence properties of the as-prepared phosphors were investigated. The Rietveld refinements of the powder X-ray diffraction (XRD) data demonstrated the single phase of the samples, and two crystallographic sites of La3+ were observed in the crystal structure. Under the excitation of UV light, both Ba0.45Ca2.5La6(SiO4)6: 0.05 Eu2+ and Ba1.45Ca1.5La6(SiO4)6: 0.05 Eu2+ phosphors emitted cyan light due to the 4f65 d1→4f7 transitions of the Eu2+ ion. The emission spectra could be well fitted by two component Gaussian peaks corresponding to two different coordination environments of the Eu2+ ions. The temperature-dependent photoluminescence spectra show a large difference on the thermal stability between the two phosphors. The two phosphors exhibit effective absorption of near-UV light and their internal quantum efficiencies (IQEs) were calculated as 31.5% and 42.4% under 295 nm UV-light excitation. The experimental results indicate that the novel cyan phosphors might have potential applications in white light-emitting diodes (LEDs) based on the near-UV LED chip.

The application of phase-change materials (PCMs) for solar energy utilization and thermal energy storage is limited by their low thermal conductivity, undesirable solar-thermal conversion efficienc...

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.

Lightweight structural materials are critical in construction and automobile applications. In past centuries, there has been great success in developing strong structural materials, such as steels, concrete, and petroleum-based composites, most of which, however, are either too heavy, high cost, or nonrenewable. Biosourced composites are attractive alternatives to conventional structural materials, especially when high mechanical strength is presented. Here we demonstrate a strong, lightweight bio-based structural material derived from bamboo via a two-step manufacturing process involving partial delignification followed by microwave heating. Partial delignification is a critical step prior to microwave heating as it makes the cell walls of bamboo softer and exposes more cellulose nanofibrils, which enables superior densification of the bamboo structure via heat-driven shrinkage. Additionally, microwave heating, as a fast and uniform heating method, can drive water out of the bamboo structure, yet without destroying the material's structural integrity, even after undergoing a large volume reduction of 28.9%. The resulting microwave-heated delignified bamboo structure demonstrates outstanding mechanical properties with a nearly 2-times improved tensile strength, 3.2-times enhanced toughness, and 2-times increased bending strength compared to natural bamboo. Additionally, the specific tensile strength of the modified bamboo structure reaches 560 MPa cm3 g-1, impressive given that its density is low (1.0 g cm-3), outperforming common structural materials, such as steels, metal alloys, and petroleum-based composites. These excellent mechanical properties combined with the resource abundance, renewable and sustainable features of bamboo, as well as the rapid, scalable manufacturing process, make this strong microwave-processed bamboo structure attractive for lightweight, energy-efficient engineering applications.

Water shortage is one of the most pressing challenges across the world. Wood, a natural and sustainable material, possesses a unique hierarchical three-dimensional (3D) interconnected microstructur...

The modifications of local structure in solid solution are a crucial step to regulate the photoluminescence properties of rare-earth ion-based phosphors. However, the structural diversity of host matrices and the uncertain occupation of activators make it challenging to obtain phosphors with both high stability and tailored emission. Herein, We synthesized a series of β-Ca

A stronger, cooler wood One good way to reduce the amount of cooling a building needs is to make sure it reflects away infrared radiation. Passive radiative cooling materials are engineered to do this extremely well. Li et al. engineered a wood through delignification and re-pressing to create a mechanically strong material that also cools passively. They modeled the cooling savings of their wood for 16 different U.S. cities, which suggested savings between 20 and 50%. Cooling wood would be of particular value in hot and dry climates. Science , this issue p. 760

Three-dimensional integrated electrode materials have broad application prospects in the field of improving the specific energy of lithium-ion batteries. Metal-organic frameworks and their derivatives are potential anode materials for Li-ion batteries due to their highly controllable composition and structure. Here, we designed and synthesized the Co3O4@carbonized wood (Co3O4@CW) composite as the anode materials of Li-ion batteries by ZIF-67 in situ growth in the balsa wood and high-temperature carbonization. The composite keeps the low-tortuosity and porous structure with a high specific surface area (293.61 m2/g), providing a smooth electrolyte transport path and enabling sufficient reaction sites for lithium-ions, thereby enhancing the electrochemical reactivity. The integrated electrode exhibits a specific capacity of 486.65 mAh/g and good stable performance (90.71% capacity maintain rate) after 200 cycles at the current of 0.2 A/g. The specific capacity reaches 552.37 mAh/g at 0.1 A/g and possessed excellent pseudocapacitive capacity (92.3%, the pseudocapacitive contribution).

Silicoaluminophosphate zeolite (SAPO-34) has been attracting increasing attention due to its excellent form selection and controllability in the chemical industry, as well as being one of the best industrial catalysts for methanol-to-olefin (MTO) reaction conversion. However, as a microporous molecular sieve, SAPO-34 easily generates carbon deposition and rapidly becomes inactivated. Therefore, it is necessary to reduce the crystal size of the zeolite or to introduce secondary macropores into the zeolite crystal to form a hierarchical structure in order to improve the catalytic effect. In this review, the synthesis methods of conventional SAPO-34 molecular sieves, hierarchical SAPO-34 molecular sieves and nanosized SAPO-34 molecular sieves are introduced, and the properties of the synthesized SAPO-34 molecular sieves are described, including the phase, morphology, pore structure, acid source, and catalytic performance, in particular with respect to the synthesis of hierarchical SAPO-34 molecular sieves. We hope that the review can provide guidance to the preparation of the SAPO-34 catalysts, and stimulate the future development of high-performance hierarchical SAPO-34 catalysts to meet the growing demands of the material and chemical industries.

The luminescence spectra of some trivalent rare-earth ions in a garnet host present interesting multisite structures; however, their mechanism is still not fully understood. In this study, for the first time, we directly observed two luminescence centers of Ce3+ at a single site in a novel garnet Ca3Sc2Ge3O12 phosphor. The spectral characteristics of the two luminescence centers were clearly identified using site-selective and time-resolved spectroscopy. Luminescence excitation was observed at 425 nm and 450 nm, corresponding to emissions at 490 (Ce(i)) nm and 530 (Ce(ii)) nm. The decay curves confirmed the existence of energy transfer from Ce(i) to Ce(ii). The potential mechanisms of the multisite luminescence are also discussed. This study gives a new insight into the concentration-dependent red-shift and inhomogeneous broadening of the Ce3+ emission band in the garnet phosphor. The title phosphor showed excellent thermal stability, with more than 90% of the initial intensity at the functioning temperature (323 K). Finally, a white LED lamp was fabricated, which exhibited an excellent color rendering index (82.3) and a proper correlated color temperature (3582 K). These results demonstrate that Ca3Sc2Ge3O12:Ce3+ is highly promising to serve as a blue-pumped phosphor for white LEDs.

The shortage of clean water is one of the predominant causes of human mortality, especially in remote rural areas. Currently, solar steam generation is being adopted as an efficient, sustainable, and low-cost means for water desalination to produce clean water. However, preventing salt accumulation during operation while maintaining long-term stability and a rapid evaporation rate is a critical challenge that needs to be urgently addressed to further facilitate the practical applications of solar desalination, especially for desalinating high-salinity brine. Here, we demonstrate that a bimodal porous structure (e.g., balsa wood) can serve as an efficient and stable solar vapor generator for high-salinity brine desalination. Taking advantage of the inherent bimodal porous and interconnected microstructures of balsa wood, rapid capillary transport through the microchannels and efficient transport between the micro- and macrochannels through ray cells and pits in the bimodal evaporator can lead to quick replenishment of surface vaporized brine to ensure fast and continuous clean water vapor generation. The bimodal evaporator demonstrates a rapid evaporation rate of 6.4 kg m−2 h−1 under 6 suns irradiation and outstanding long-term stability for desalination of high salinity brine. The large vessel channels play a critical role in preventing salt from accumulating, as evidenced by controlled experiments with large vessels either blocked in the bimodal evaporator (balsa evaporator) or absent in a unimodal evaporator (e.g., cedar wood) whose porous structure occurs naturally without large vessels. Both approaches demonstrate severe salt accumulation during solar desalination due to a lack of sufficient brine replenishment from the bulk solution beneath. With its unique bimodal porous and interconnected microstructure configuration obtained by a facile and scalable fabrication method, our bimodal porous structured evaporator device represents an efficient, stable, low-cost, and environmentally friendly solar vapor generator for high-salinity brine desalination.

Thermal quenching is one of the most critical challenges for the application of materials under high temperatures. Particularly, BaMgAl10O17:Eu2+ (BAM) has been well considered the preferred blue-emitting phosphor in tricolor fluorescent lamps, plasma display panels (PDP), and many other lighting and display devices due to its excellent luminescence efficiency and satisfactory chromaticity. However, its wide application range is still constrained by two major problems. Firstly, the synthesis temperature for BAM is too high. Commercial BAM materials are typically prepared with high-temperature solid-phase methods over 1550°Ctemperatures. Secondly, co-solvent, which is added during the synthetic process to dissolve the solid phases, is prone to thermal deterioration. To tackle these problems, we propose the cationic substitution method combined with co-solvent-assisted sintering to improve the thermal stability of BAM. In the end, we obtained a novel BAM material with a comparably lower synthesis temperature and satisfactory thermal stability. In our work, the thermal stability of BAM synthesized with 5% boric acid substituted by 0.08 mol Ca2+ was significantly higher compared with that synthesized without calcium substitution. Additionally, the activation energies ( Δ E ) of Ba0.92Ca0.08MgAl10O17:Eu2+ and Ba0.92Sr0.08MgAl10O17:Eu2+ were calculated to be approximately 0.26 eV and 0.35 eV, respectively, indicating that the BAM substituted with Sr2+ is more thermally stable.

Nanosized cobalt (II, III) oxide (Co3O4) is a promising anode material in virtue of its relatively high theoretical capacity. In this study, nanosized Co3O4 was fabricated by facile hydrothermal method followed by annealing. So-obtained samples exhibited integrated characteristics and advantages including porous nanosheets structure, oxygen vacancy, and pseudocapacitance Pseudo-capacitance. The splendid electrochemical properties of Co3O4 electrodes are inseparable from these features providing synergistic effect. During insertion and extraction of lithium ion, porous nanosheets structure not only assisted in buffering volume changes, but also benefitted the transportation of electron/ion. Furthermore, abundant oxygen vacancies improved internal conductivity and promoted migration of lithium ion via regulating surface electronic structure. The pseudocapacitance behavior was instrumental in electrochemical kinetics. Consequently, the resulting nanosized Co3O4 delivered fine discharge specific capacity (1502.5 mAh g−1) after 100 cycles at 200 mA g−1 accompanied by the superior capacity retention rate (97.8%). Discharge specific capacity (1093.5 mAh g−1) higher than that of graphite, was recorded even at a current density of 2 A g−1. The results indicate that the as-obtained MNS-CoO1.0M with excellent properties may act as promising alternative candidates for lithium storage materials.

Due to its high theoretical capacity (4200 mAh g−1), appropriate charging potential (∼0.5 V vs Li+/Li), and abundant raw material sources, silicon anode material is considered to be an ideal anode material for lithium-ion batteries. However, its low intrinsic conductivity and huge volume expansion (∼300%) during the lithiation process seriously reduce the cycle life of the battery, causing the battery's capacity to rapidly decay. In this work, 3D pomegranate-like structured Si@void@Ni@C microspheres are designed and synthesized through hydrothermal and carbonization methods. In this unique structure, the supporting layers, including carbon and nickel layers, can not only improve conductivity but also offer sufficient space to alleviate the volume expansion of silicon particles during the lithium insertion/extraction process. Combined with the above advantages, the 3D pomegranate-like structured Si@void@Ni@C microspheres anode shows excellent electrochemical performance, such as high first discharge capacity (1697 mAh g−1), fine cycle stability (0.23% capacity attenuation rate for each cycle), and excellent rate performance (97.7% capacity recovery rate).

Broadband near-infrared light (NIR) near 800 nm has broad application prospects in food detection and night vision monitoring. Compared with NIR chips, NIR phosphors have distinct advantages, including low cost, a mature synthesis process, and tunable combination. However, at present, oxide NIR phosphors have some disadvantages, such as a narrow full width at half maximum (FWHM), poor thermal stability, and low photoelectric efficiency. Herein, K3ScF6:Cr3+ NIR phosphors with a cubic structure were synthesized using the hydrothermal method. These phosphors can be effectively excited by blue light (430 nm) and red light (630 nm), leading to a broadband Cr3+ emission from 650 nm to 950 nm with a large FWHM of 430 nm. They also exhibit excellent thermal stability and retain 87.3% of their initial intensity at 150 °C. Under a driving current of 100 mA, their photoelectric efficiency can reach 9.315% of that of fabricated NIR light-emitting diodes (NIR-LED). An NIR-LED device based on this phosphor can thus be implemented in night vision imaging systems.