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An in situ gel separator based on an electrospun three-layer nanofibrous membrane (PSE11-Gel) is developed for high-performance lithium-organic batteries (LOBs). The highly efficient shuttle effect inhibition of organic cathode molecules or lithiated intermediates has been demonstrated for PSE11-Gel to realize high-capacity stable LOBs. [ABSTRACT FROM AUTHOR]

The article focuses on evaluating the anterior dentoalveolar relationship in skeletal Class III malocclusion patients with different vertical facial patterns using cone-beam computed tomography (CBCT). Topics include measuring and comparing labiolingual inclinations of the teeth and alveolar bone, as well as analyzing the anterior dentoalveolar inclination among patients with hypodivergent, normodivergent, and hyperdivergent facial patterns.

Monodispersed Pt colloids with a mean size of 2 nm were deposited uniformly on the {110} facets of a rod-shaped rutile TiO2, forming a well-defined Pt/TiO2 system. Oxidative treatment of this precursor at elevated temperatures re-dispersed the Pt particles into clusters and single-atoms. Air-calcination at 673 K partially oxidized the Pt particle surface, while calcination at 773 K yielded PtOx clusters of 1.6 nm in 7–8 atomic layers. Further calcination at 873 K formed a mixture of raft-like PtOx clusters (1.6 nm, 1–2 atomic layers) and cationic single-atoms. When tested for CO oxidation at 373 K, the Pt particles showed a higher activity than the PtOx clusters, whereas the cationic single-atoms were much less active. Subsequent H2-reduction at 473 K converted the partially oxidized Pt particles into the metallic species, but they were encapsulated by TiO2−x overlayers because of the strong metal–support interactions, which decreased the activity dramatically. H2-reduction of the PtOx clusters at 473 K enhanced the fraction of metallic Pt species without changing the size and geometry, and promoted the activity substantially. H2-treatment of Pt single-atoms at 473 K increased the activity only moderately because most Pt species still kept at cationic species. These results straightforwardly differentiated the catalytic behavior of Pt particles, clusters and single-atoms at the same metal loading and over the same TiO2 support, and further demonstrated that the electronic structures of Pt entities played a decisive role in the catalytic oxidation, in addition to the specified sizes. [ABSTRACT FROM AUTHOR]

Terahertz (THz) technologies provide opportunities ranging from calibration targets for satellites and telescopes to communication devices and biomedical imaging systems. A main component will be broadband THz absorbers with switchability. However, optically switchable materials in THz are scarce and their modulation is mostly available at narrow bandwidths. Realizing materials with large and broadband modulation in absorption or transmission forms a critical challenge. This study demonstrates that conducting polymer‐cellulose aerogels can provide modulation of broadband THz light with large modulation range from ≈ 13% to 91% absolute transmission, while maintaining specular reflection loss < −30 dB. The exceptional THz modulation is associated with the anomalous optical conductivity peak of conducting polymers, which enhances the absorption in its oxidized state. The study also demonstrates the possibility to reduce the surface hydrophilicity by simple chemical modifications, and shows that broadband absorption of the aerogels at optical frequencies enables de‐frosting by solar‐induced heating. These low‐cost, aqueous solution‐processable, sustainable, and bio‐friendly aerogels may find use in next‐generation intelligent THz devices. [ABSTRACT FROM AUTHOR]

Pd25Cu75@SiO2 core–shell and PdCu@SiO2@Cu core–shell–satellite architectures were fabricated by silica-coating of Pd25Cu75 colloids in a reverse microemulsion. Hydrolysis of tetraethylorthosilicate in the reverse microemulsion containing hydrazine and ammonia yielded a core–shell structure, while the use of ammonia only, instead of a mixture of hydrazine and ammonia, formed a core–shell–satellite structure. The ammonia-leached copper species migrated onto the developing silica shell and formed smaller Cu clusters. Air-calcination at 673 K followed by H2-reduction at 773 K of the as-synthesized samples removed the organic surfactants and generated the permeable porous silica shells. The core–shell catalyst consisted of a metal core (8.5 nm) and a silica shell (7.8 nm), while the core–shell–satellite catalyst was composed by a metal core (7.0 nm), a silica shell (8.0 nm), and satellite Cu clusters (1.4 nm) on the silica shell. When used to catalyze the selective hydrogenation of acetylene to ethylene, the core–shell–satellite catalyst showed substantially enhanced activity and stability because of the synergetic catalysis between the metal core and the surrounding Cu clusters. [ABSTRACT FROM AUTHOR]

Surface ligands play an important role in shape‐controlled growth and stabilization of colloidal nanocrystals. Their quick removal tends to cause structural deformation and/or aggregation to the nanocrystals. Herein, we demonstrate that the surface ligand based on poly(vinylpyrrolidone) (PVP) can be slowly removed from Pd nanosheets (NSs, 0.93±0.17 nm in thickness) by simply aging the colloidal suspension. The aged Pd NSs show well‐preserved morphology, together with significantly enhanced stability toward both e‐beam irradiation and electrocatalysis (e.g. ethanol oxidation). It is revealed that the slow desorption of PVP during aging forces the re‐exposed Pd atoms to reorganize, facilitating the surface to transform from being nearly perfect to defect‐rich. The resultant Pd NSs with abundant defects no longer rely on surface ligand to stabilize the atomic arrangement and thus show excellent structural and electrochemical stability. This work provides a facile and effective method to maintain the integrity of colloidal nanocrystals by slowly removing the surface ligand. [ABSTRACT FROM AUTHOR]

Single crystal silicon is an important material used for semiconductor devices and also a potential material in device research. Far-infrared optical properties are studied for the helium ion implanted samples with different fluences of 5.0 x [10.sup.16], 1.0 x [10.sup.17], 2.0 x [10.sup.17], and 4.0 x [10.sup.17] [cm.sup.-2]. The absorption coefficient and refractive index of silicon with different helium concentrations are measured in the wave number range from 4 to 85 [cm.sup.-1] and temperature range from 145 to 520 K. The results show that the absorption coefficient increases with increasing fluence of helium ions, but the refractive index decreases. The correlations between absorption coefficient and refractive index and temperature of all samples are similar. The refractive index increases with temperature in the whole measurement temperature range, but the absorption coefficient has different trends in the different wavebands. The absorption coefficient decreases with the increase of temperature in the region below 12 [cm.sup.-1]; however, the absorption coefficient increases when the wave number is larger than 30 [cm.sup.-1]. The absorption coefficient curves at different wavebands are well fitted by the Drude model. A large number of helium bubbles and defects, such as voids and dislocations have been observed in the implanted area by transmission electron microscopy (TEM), which contributes to the increase of optical absorption. PACS Nos.: 85.40.Ry, 91.60.Mk, 68.47.Fg. Le monocristal de silicium est un materiau important pour les applications semi-conductrices et qui a beaucoup de potentiel en recherche sur les dispositifs. Nous etudions ici les proprietes dans l'infrarouge lointain d'echantillons avec implantation d'ions helium a des fluences de 5.0 x [10.sup.5], 1.0 x [10.sup.17], 2.0 x [10.sup.17] et 4.0 x 1017 [cm.sup.-2]. Nous mesurons le coefficient d'absorption et l'indice de refraction du silicium avec differentes concentrations d'helium, pour des nombres d'onde allant de 4 a 85 [cm.sup.-1] et des temperatures de 145 a 520 K. Les resultats indiquent que le coefficient d'absorption augmente avec la fluence en helium, alors que l'indice de refraction diminue sous les memes conditions. Les correlations entre le coefficient d'absorption, l'indice de refraction et la temperature demeurent les memes pour tous les echantillons. L'indice de refraction augmente avec la temperature pour tout le domaine etudie, mais le coefficient d'absorption a differentes tendances selon le domaine de longueurs d'onde. Le coefficient d'absorption diminue lorsque la temperature augmente dans la region sous 12 [cm.sup.-1]. Sous la meme augmentation de temperature, le coefficient d'absorption augmente dans la region au del;! de 30 [cm.sup.-1]. Les courbes du coefficient d'absorption dans les differents domaines de longueur d'onde sont bien ajustees par le modele de Drude. A l'aide de la microscopie par transmission electronique (TEM), nous observons beaucoup de bulles d'helium et de defauts, comme des lacunes et des dislocations dans les regions d'implantation, ce qui contribue a l'augmentation de l'absorption optique. [Traduit par la Redaction], 1. Introduction Silicon is a major material applied in far-infrared devices [1] and extensively used as windows, quasi-optic lenses, and dielectric cavities [2]. A silicon thermopile infrared detector was fabricated [...]

Flexible sensors play an important role in collecting stimuli information and sending them to a central processing unit or cloud for analysis and decision‐making. As much information is needed to be collected, the fabrication of multiparameter flexible sensors is becoming increasingly urgent. To this end, conducting polymer‐based composites have been proven as promising materials for developing pressure‐temperature dual‐parameter sensors. However, fabrication of ideal dual‐parameter sensors with fully decoupled pressure‐temperature readings, good sensitivity, and a simple preparation process remain challenges. Here, a strategy of fabricating a pressure‐temperature dual‐parameter sensor based on conformal printing of conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on the surface of microstructured polydimethylsiloxane (PDMS) substrate is demonstrated. It is found that secondary doped PEDOT:PSS provides temperature‐independent conductivity. Combined with the sea‐island microstructured PDMS substrate, a screen‐printed flexible sensor demonstrates fully decoupled pressure‐temperature reading ability, competitive sensitivity, and good stability. The excellent sensing properties of the devices, with a maximum pressure sensitivity of 134.25 kPa−1 and linear response region over 300 kPa as well as highly sensitive temperature sensing for finger touch, together with their unique advantages of low‐cost and large‐area fabrication, make the printed flexible dual‐parameter sensors promising applications in electric‐skin (e‐skin), human‐machine interaction, and robotics. [ABSTRACT FROM AUTHOR]