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The interface characteristics of electrode materials are of tremendous value for supercapacitors, however, poor conductivity, instability in harsh reaction conditions and limited ion mobility in oxide materials are identified as immense challenges for generating high energy density without renouncing the power capability. Herein, a peculiar catalytic chemical vapour deposition (CCVD) approach is employed to decorate a very thin carbon capsules (CCs) on the surface of LiMn2O4 nanorods to synthesize a very active and uniformly distributed LiMn2O4/CCs nano-hybrid material with modified interface characteristics. The CCs not only provide the physicochemical protection as well as improve the electrical conductivity. As an electrode material, LiMn2O4/CCs possess the specific discharge capacitance of 451 F/g which is far superior to LiMn2O4 (304 F/g) at the current density of 0.5 A/g in 0.5 M Li2SO4 aqueous solution. In addition, the LiMn2O4/CCs exhibit an outstanding specific capacitance of 380 F/g even at a much higher current density of 8 A/g. Moreover, after 3000 charge and discharge cycles, LiMn2O4/CCs electrode retains nearly 95% of initial capacity, higher than that of spinel LiMn2O4 electrode which retains only 93%. This innovative technique can be adopted to construct a large variety of other nano-hybrid materials for consumer utilization in the field of supercapacitors.

Achieving highly efficient Y3Al5O12:Ce3+ phosphor is desirable to fabricate bright white light-emitting diodes (wLED). Designing a synergistic effect of energy transfer from the guest materials to the host Y3Al5O12:Ce3+ is expected to favor the higher quantum efficiency of Y3Al5O12:Ce3+ phosphor. Here, we report a novel strategy to enhance the emission intensity and quantum efficiency of Y3Al5O12:Ce3+ phosphor by coating a thin g-C3N4 layer on the surface of Y3Al5O12: Ce3+ particles. Melamine was coated on the surface of Y3Al5O12: Ce3+ and heated at 580 °C to develop the g-C3N4 layer. The phase, microstructure, photoluminescent properties and thermal stability are investigated in detail. It is demonstrated that g-C3N4 coated Y3Al5O12: Ce3+ has been successfully achieved, which shows higher emission intensity and quantum efficiency than the uncoated sample. This is due to the strong excitation energy absorption of g-C3N4, which is then transferred to luminescent Ce3+ ions. The synergistic effect of g-C3N4 coating-host materials shows potential applications to improve the quantum efficiency of other phosphors.

Membranes of ceramic foams exhibit excellent prospects for application in the field of high-temperature particulate matter (PM) capture. Production of ceramic membranes that can achieve good removal efficiency as well as low pressure drop in high-efficiency PM filtration represents a great challenge. This paper reports on the preparation of porous-foam mullite-bonded SiC-ceramic membranes (MSCMs) with a 3D interconnecting pore network by a direct foaming method combined with gel-tape casting. The produced MSCMs contained large pores with a diameter of 60–150 µm, which were interconnected with abundant small functional (for filtering) pores of

Superior thermal quenching and degradation of phosphors are required for long lifetime lighting devices, such as light-emitting diodes, which can be realized through composition modification. Here, Al-N bonds in AlON: Eu 2+ phosphors are substituted by higher bond order of Si-C. Photoluminescence (PL) results show thermal quenching (at 150 °C) and thermal degradation (after 600 °C treatment in air) are improved by 5% and 8% with a small decrease of PL intensity in 5% SiC doped AlON: Eu 2+ phosphor. To explain these observations, first-principles computational study was performed to understand the Si and C configuration in AlON:Eu 2+ . The calculations reveal that Si and C elements are not randomly distributed in AlON lattice. It was found that Si prefers occupying tetrahedral sites (Td-Si) and the insertion of C in Td-Si is always energetically favorable, which results in the formation of SiC 4 and SiNC 3 clusters. Thus, the Al-N substitution by Si-C induces a stronger local structure, which accounts for the emission redshift and better thermal stability.

Generally speaking, thermal stability is the key factor for microwave absorbers (MAs) at high temperature. In this paper, we first propose to apply a novel material called Cr2AlC (CAC) in the high temperature field. The self-made high purity CAC powder prepared by salt bath exhibits good microwave absorption performance and outstanding. Thermogravimetric (TG) analysis indicates the CAC begins to oxidize significantly above 800 °C. Moreover, the effective medium theory is adopted to calculate the microwave absorption performance for the CAC/paraffin composite material. We found that the sample with 70 wt% CAC (CAC70) has a minimum reflection loss of −25.09 dB at 11.08 GHz and its effective absorption bandwidth (below −10 dB) is 2.2 GHz (10.2–12.4 GHz) at the thickness of 2.00 mm, which indicates a thin layer of Al2O3 at room temperature will not affect the entry of electromagnetic waves and internal electrical losses. The high anti-oxidation layered structure CAC provides an opportunity to expand microwave absorption in high temperature applications.

The Eu2+-doped G-La2Si2O7 phosphor was successfully prepared through the high-temperature solid-state reaction method with the aid of AlF3 flux. The results of Eu L3-edge XANES characterization showed that only Eu3+ can be detected in as-received G-La2Si2O7 phosphor and that Al2O3 addition leads to a partial reduction of Eu3+ to Eu2+, while complete reduction occurs with AlF3 addition. The obtained Eu2+-doped G-La2Si2O7 phosphor exhibited typical Eu2+ blue-green emission under the near-UV light excitation. The analysis of Fourier transform infrared spectroscopy (FT-IR) and 27Al nuclear magnetic resonance (NMR) results suggests that Al occupies the Si sites and F occupies the O sites. The positive influence of Al–F doping is related to the structure of the produced phosphors, which was analyzed with the aid of first-principles density functional calculations. The results of the theoretical calculations are a good match to the experimental findings.

Designing of materials which can resist aging and corrosion in harsh reaction conditions is required to mitigate the omnipresent issue of electromagnetic interference pollution. Particularly, FeSiAl alloy is a relevant composite material, however, it always suffers aging and corrosion when exposed to crude saline environment. Herein, Carbon-encapsulated FeSiAl (FeSiAl@C) hybrid flakes are developed by catalytic chemical vapor deposition (CCVD) technique through the reaction of FeSiAl precursor with acetylene (C2H2) gas at 300 °C for 5 min. The carbon coating efficiently improves the impedance matching characteristics of FeSiAl powder leading to enhance microwave absorption. Not only that, the carbon capsule also plays an effective shielding function to prevent the alloy from corroding. Specifically, the FeSiAl@C-300 °C delivers increased complex permeability and permittivity in the frequency range of 7–14 GHz, as well as improved impedance matching. In addition, the corrosion resistance is measured using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in 5 wt% NaCl solution. The results indicate that the synthesized hybrid exhibits excellent corrosion resistance capability. So, the composite synthesis is a worthy approach to design hybrid materials for effective microwave absorption and corrosion resistance properties for practical applications.