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This paper presents a top‐down fabrication and an isolation process for producing billions of multifunctional dot light‐emitting diodes (LEDs) without a sacrificial layer. The process involves a combination of electrochemical etching (ECE) of an n‐GaN layer and sonochemical separation of an etched porous layer to isolate the dot LEDs. The structure of the developed dot LEDs can be expressed as Au/indium tin oxide (ITO)/p‐GaN/multiple quantum well (MQW)‐InGaN/n‐GaN@SiO2. The nanopore size, separation ratio, and emission characteristics of dot LEDs produced by ECE are investigated, as well as the solvent type on ultrasonic separation in the sonochemical process. Blue electroluminance devices fabricated in a vertical structure using dot LEDs exhibit a peak external quantum efficiency (EQE) of 6.21% at an applied voltage of 4.0 V, and a luminous efficacy of 1070 cd m−2, at an applied voltage of 10.0 V. Although the current technology for blue dot LEDs may not produce a higher EQE than the existing display technologies, it is essential to consider that the development of dot LED displays is still in its early stages. Furthermore, the findings show that the dot LEDs have the potential to significantly reduce material costs and provide new opportunities for nanoscale GaN‐based LED displays. [ABSTRACT FROM AUTHOR]

The optical features of multiple‐layered axial heterostructures composed of III‐nitride semiconductors (GaN, InGaN, and AlGaN) are investigated to realize tunable nanolasers. The optical confinement effects develop exciton‐polariton in nanorods, leading to polariton lasing with distinctive dispersion. The lasing characteristics in the heterostructure are similar to those in the homostructure, although the carrier transfer between layers influences the optical gain. The energy‐dependent property of polariton changes the mode spacing of lasing peaks. The alloyed systems of InGaN can tune the color of lasing in the visible region, while the lasing of AlGaN is also achievable in the optimized configuration. The polarization of lasing indicates the predominant contribution of the fundamental transverse mode. Therefore, in the multiple‐layered heterostructure, controllable triple‐color lasing using the feature of polariton, modulation of band gap energy, and the amplification process of the waveguide is demonstrated for the first time, with the tunable color over a wide range of the visible region. Multicolor polariton nanolasers offer a promising path to diverse nanophotonic devices with controllable optical characteristics. [ABSTRACT FROM AUTHOR]

A combined process of nanoimprint lithography and dual‐side aligned photolithography to address misalignment of subsequent layers for the fabrication of SiNx nanoporous membrane filters (SiNx nanofilter) is suggested. Here, in one process, 21 SiNx nanofilter chips are fabricated on a 6 inch Si wafer by aligning nanopore area of nanofilter and template area of nanofilter chip. An SiNx nanofilter chip‐integrated fluidic device is used to test the purification ability of the nanofilter in terms of its pore size and surface hydrophobicity or hydrophilicity. This is the first attempt at separating unnecessary chemical residues from a mixed reactant solution by nanoscale purification process using the tremendous number of nanoholes in the nanofilter. After purification by the nanofilter, high efficiency and narrow‐band Cs3MnBr5 phosphor is synthesized by evaporative crystallization. Here, the photoluminescent quantum yield (PLQY) of the purified Cs3MnBr5 phosphor is monitored to evaluate the purification ability of the SiNx nanofilter. The highest PLQY (53%) of Cs3MnBr5 green phosphors is obtained by purification of reactant solution using nanofilter with 50 nm nanopore diameter and hydrophilic surface. This combined process proves its potential for scalable manufacturing of complex designed SiNx nanofilter chips for chemical species sieving and other applications. [ABSTRACT FROM AUTHOR]

The development of materials capable of varying macroscale ligand distributions can emulate an extracellular matrix (ECM) remodeling and regulate the adhesion and polarization of macrophages. In this report, negatively charged slidable nano‐ligands are assembled and then conjugated to a positively charged substrate via electrostatic interaction. The negatively charged slidable nano‐ligands are prepared by coating magnetic nanoparticles with a polymer linker and negatively charged RGD ligand. The nano‐ligand sliding is characterized under an external magnetic field, which spatiotemporally alters macroscale ligand density. To the best of knowledge, this is the first demonstration that magnetic maipulation of the macroscale ligand density inhibits inflammatory M1 phenotype but stimulates the adhesion and regenerative M2 phenotype of host macrophages. Furthermore, it is elucidated that the magnetic attraction of the slidable nano‐ligand facilitates the assembly of adhesion structures in macrophages, thereby stimulating their regenerative M2 phenotype. The design of ECM‐emulating materials that allow remote, spatiotemporal, and reversible controllability of macroscale ligand density provides an appealing strategy in the spatiotemporal regulation of immunomodulatory tissue‐regenerative responses to implants in vivo. [ABSTRACT FROM AUTHOR]

Highly efficient bright green-emitting ZnAgInS (ZAIS)/ZnInS (ZIS)/ZnS alloy core/inner-shell/shell quantum dots (QDs) are synthesized using a multistep hot injection method with a highly concentrated zinc acetate dihydrate precursor. ZAIS/ZIS/ZnS QD growth is realized via five sequential steps: a core growth process, a two-step alloying-shelling process, and a two-step shelling process. To enhance the photoluminescence quantum yield (PLQY), a ZIS inner-shell is synthesized and added with a band gap located between the ZAIS alloy-core and ZnS shell using a strong exothermic reaction. The synthesized ZAIS/ZIS/ZnS QDs shows a high PLQY of 87% with peak wavelength of 501 nm. Tripackage white down-converted light-emitting diodes (DC-LEDs) are realized using an InGaN blue (B) LED, a green (G) ZAIS/ZIS/ZS QD-based DC-LED, and a red (R) ZnCuInS/ZnS QD-based DC-LED with correlated color temperature from 2700 to 10 000 K. The red, green, and blue tripackage white DC-LEDs exhibit high luminous efficacy of 72 lm W−1 and excellent color qualities (color rendering index (CRI, Ra) = 95 and the special CRI for red ( R9) = 93) at 2700 K. [ABSTRACT FROM AUTHOR]

Dual align key, Cs 3MnBr 5, green phosphor, nanoimprint lithography, nanoporous filter, membrane filter Keywords: dual align key; Cs 3MnBr 5; green phosphor; nanoimprint lithography; nanoporous filter; membrane filter EN dual align key Cs 3MnBr 5 green phosphor nanoimprint lithography nanoporous filter membrane filter 1 1 1 07/14/22 20220701 NES 220701 B Nanoporous Filters b The frontispiece presented by Young Rag Do and co-workers (article number 2101519) shows filtration images of reactant ionic solutions with 2D SiN I SB x sb i nanofilters, used to synthesize Cs SB 3 sb MnBr SB 5 sb phosphors via eco-friendly water-based evaporative crystallization process. Fabrication of SiNx Nanopore Filters Using Combined Process of Nanoimprint and Dual-Side Aligned Photolithography for Purified Cs3MnBr5 Green Phosphors (Adv. [Extracted from the article]

To enhance both adhesive strength and flexural strength, a new structure consisting of two layers with different degree of crystallization was investigated as a substrate material for low-temperature co-fired ceramics (LTCC). A mixture system of silica-based glass and AlO crystalline powder, which is known to be crystallized during the sintering process was used. Glasses with different compositions and various amounts of alumina filler were used for our new structure. Crystallization behavior was monitored by means of powder X-ray diffraction. The microstructure of sintered body after electroless plating was examined by scanning electron microscopy. It was observed that the degree of crystallization was strongly affected by glass composition and amount of alumina filler but sintering behavior depended on glass composition rather than amount of alumina. The combination of layers with 40 wt% alumina and 45 wt% alumina as an inner layer and outer layer, relatively, shows 362 MPa flexural strength and 1.74 kgf adhesion strength. [ABSTRACT FROM AUTHOR]

Aging is defined as changes in an organism over time. The proportion of the aged population is markedly increasing worldwide. The kidney, as an essential organ with a high energy requirement, is one of the most susceptible organs to aging. It is involved in glucose metabolism via gluconeogenesis, glucose filtration and reabsorption, and glucose utilization. Proximal tubular epithelial cells (PTECs) depend on lipid metabolism to meet the high demand for ATP. Recent studies have shown that aging‐related kidney dysfunction is highly associated with metabolic changes in the kidney. Peroxisome proliferator‐activated receptor gamma coactivator‐1 alpha (PGC‐1α), a transcriptional coactivator, plays a major role in the regulation of mitochondrial biogenesis, peroxisomal biogenesis, and glucose and lipid metabolism. PGC‐1α is abundant in tissues, including kidney PTECs, which demand high energy. Many in vitro and in vivo studies have demonstrated that the activation of PGC‐1α by genetic or pharmacological intervention prevents telomere shortening and aging‐related changes in the skeletal muscle, heart, and brain. The activation of PGC‐1α can also prevent kidney dysfunction in various kidney diseases. Therefore, a better understanding of the effect of PGC‐1α activation in various organs on aging and kidney diseases may unveil a potential therapeutic strategy against kidney aging. [ABSTRACT FROM AUTHOR]

Highly efficiENt greEN ‐ emitting Zn ‐ Ag ‐ In ‐ S (ZAIS)/Zn ‐ In ‐ S (ZIS)/ZnS alloy core/inner ‐ shell/shell quantum dots (QDs), realized by an exothermically gENerated ZIS inner shell, are presENted by Y. R. Do and co ‐ workers in article 1602638. A photoluminescENce quantum yield of 87% with a peak wavelENgth of 501 nm is achieved. Candidates for applications involve white down ‐ converted light ‐ emitting diodes (DC ‐ LEDs) providing high ENergy performance and ultrahigh color quality. [ABSTRACT FROM AUTHOR]