Mn/Mg co-doped AlON ceramic with ultra-narrowband green emission combining high transparency toward a wide gamut backlight application.

Narrowband green-emission, combined with superior physicochemical stability and thermal performance, is regarded as a common pursuit in backlight display applications. However, mainstream phosphor-converted materials composed of resin or silicone resin easily encounter the dilemma of thermal decomposition and chemical corrosion for practical use. To overcome this problem, in this work, Mn/Mg co-doped AlON ceramic is successfully realized with ultra-narrowband green-emission and high transparency.

Decolorization, spectral broadening, and luminescence enhancement in Tb:YO transparent ceramics through vacuum thermal reduction.

Tb is extensively employed in magneto-optical devices and luminescent materials owing to its distinctive physical properties. However, under certain conditions, trivalent Tb readily undergoes oxidation to tetravalent Tb, significantly reducing the performance of devices containing Tb. In this Letter, we report a technique called dual-annealing (DA) post-treatment, which effectively solves Tb oxidation issues by utilizing the reducibility of the vacuum environment.

Ultrapure single-band red upconversion luminescence in Er doped sensitizer-rich ytterbium oxide transparent ceramics for solid-state lighting and temperature sensing.

Achieving single-band upconversion (UC) is a challenging but rewarding approach to attain optimal performance in diverse applications. In this paper, we successfully achieved single-band red UC luminescence in YbO: Er transparent ceramics (TCs) through the utilization of a sensitizer-rich design. The YbO host, which has a maximum host lattice occupancy by Yb sensitizers, facilitates the utilization of excitation light and enhances energy transfer to activators, resulting in improved UC luminescence.

Developing Smart Temperature Sensing Window Based on Highly Transparent Rare-Earth Doped Yttrium Zirconate Ceramics.

Lanthanide-ion-based thermometers have been widely researched and utilized as contactless temperature sensing materials. Cooperating with the unique optical and excellent physical properties of transparent ceramics, Er/Yb co-doped YZrO transparent ceramics were successfully fabricated as temperature sensing window materials. Homogeneous distribution of elements inside samples together with high transmittance (nearly 73%) makes it possible as an observing window.

Energetic Cost for Being "Redox-Site-Rich" in Pseudocapacitive Energy Storage with Nickel-Aluminum Layered Double Hydroxide Materials.

Defining the energetic landscape of pseudocapacitive materials such as transition metal layered double hydroxides (LDHs) upon redox-site enrichment is essential to harnessing their power for effective energy storage. Here, coupling acid solution calorimetry, XRD, and DRIFTS, we demonstrate that as the Ni/Al ratio increases, both as-made (hydrated) and dehydrated NiAl-LDH samples are less stable as evidenced by their enthalpies of formation. Moreover, the higher specific capacity at an intermediate Ni/Al ratio of 3 is enabled by effective water-LDH interactions, which energetically stabilize the excessive near-surface Ni redox sites, solvate intercalated carbonate ions, and fill the expanded vdW gap, paying for the "energetic cost" of being "redox-site-rich".

Optimization of the Amount and Molecular Weight of Dispersing Agent PEG During the Co-Precipitation Preparation of Nano-Crystalline C-YSZ Powder.

Single-phase nano-crystalline yttria-stabilized zirconia (YSZ) powder was prepared by co-precipitation method using zirconium oxychloride (ZrOCl₂ · 8H₂O) and yttrium nitrate (Y(NO₃)₃ · 6H₂O) as raw materials and ammonium bicarbonate (NH₄HCO₃) and liquor ammonia (NH4OH) as the precipitators. In order to get the powder with favorable dispersibility, polyethylene glycol (PEG, HO(CH₂CH₂O) n H) with different molecular weights and amounts was used as a dispersant agent in the synthesis process and its effects on the YSZ powder was investigated. The scanning electron micrograph (SEM) images showed that the degree of agglomeration and the mean crystal size of YSZ powder varied with the amount and the molecular weight of PEG.

Fast crystallization of amorphous GdZrO induced by thermally activated electron-beam irradiation.

We investigate the ionization and displacement effects of an electron-beam (e-beam) on amorphous GdZrO synthesized by the co-precipitation and calcination methods. The as-received amorphous specimens were irradiated under electron beams at different energies (80 keV, 120 keV, and 2 MeV) and then characterized by X-ray diffraction and transmission electron microscopy. A metastable fluorite phase was observed in nanocrystalline GdZrO and is proposed to arise from the relatively lower surface and interface energy compared with the pyrochlore phase.

Unique mechanical properties of nanostructured transparent MgAl2O4 ceramics.

Nanoindentation tests were performed on nanostructured transparent magnesium aluminate (MgAl2O4) ceramics to determine their mechanical properties. These tests were carried out on samples at different applied loads ranging from 300 to 9,000 μN. The elastic recovery for nanostructured transparent MgAl2O4 ceramics at different applied loads was derived from the force-depth data.

Yield Strength of Transparent MgAl2O4 Nano-Ceramic at High Pressure and Temperature.

We report here experimental results of yield strength and stress relaxation measurements of transparent MgAl2O4 nano-ceramics at high pressure and temperature. During compression at ambient temperature, the differential strain deduced from peak broadening increased significantly with pressure up to 2 GPa, with no clear indication of strain saturation. However, by then, warming the sample above 400°C under 4 GPa, stress relaxation was obviously observed, and all subsequent plastic deformation cycles are characterized again by peak broadening.