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Exploring high efficiency S‐scheme heterojunction photocatalysts with strong redox ability for removing volatile organic compounds from the air is of great interest and importance. However, how to predict and regulate the transport of photogenerated carriers in heterojunctions is a great challenge. Here, density functional theory calculations were first used to successfully predict the formation of a CdS quantum dots/InVO4 atomic‐layer (110)/(110) facet S‐scheme heterojunction. Subsequently, a CdS quantum dots/InVO4 atomic‐layer was synthesized by in‐situ loading of CdS quantum dots with (110) facets onto the (110) facets of InVO4 atomic‐layer. As a result of the deliberately constructed built‐in electric field between the adjoining facets, we obtain a remarkably enhanced photocatalytic degradation rate for ethylene. This rate is 13.8 times that of pure CdS and 13.2 times that of pure InVO4. In‐situ irradiated X‐ray photoelectron spectroscopy, photoluminescence and time‐resolved photoluminescence measurements were carried out. These experiments validate that the built‐in electric field enhanced the dissociation of photoexcited excitons and the separation of free charge carriers, and results in the formation of S‐scheme charge transfer pathways. The reaction mechanism of the photocatalytic C2H4 oxidation is investigated by in‐situ electron paramagnetic resonance. This work provides a mechanistic insight into the construction and optimization of semiconductor heterojunction photocatalysts for application to environmental remediation. [ABSTRACT FROM AUTHOR]

Development of metal oxide semiconductors‐based methane sensors with good response and low power consumption is one of the major challenges to realize the real‐time monitoring of methane leakage. In this work, a self‐assembled mulberry‐like ZnO/SnO2 hierarchical structure is constructed by a two‐step hydrothermal method. The resultant sensor works at room temperature with excellent response of ~56.1% to 2000 ppm CH4 at 55% relative humidity. It is found that the strain induced at the ZnO/SnO2 interface greatly enhances the piezoelectric polarization on the ZnO surface and that the band bending results in the accumulation of chemically adsorbed O2− ions close to the interface, leading to significant improvement in the sensing performance of the methane gas sensor at room temperature. [ABSTRACT FROM AUTHOR]

Transition metal oxides, especially bimetal oxides, are considered as one of the most promising anode materials for high‐performance lithium‐ion batteries (LIBs) due to their ultra‐high theoretical capacity. However, it is difficult to achieve fast charging at high rates due to the issues of poor electrical conductivity, large volume expansion, and poor reaction kinetics. The design of advanced nanostructured anode materials is very important to boost lithium storage performance. Herein, the multi‐hierarchical heterostructure material NiCo2O4/ZnCo2O4/Carbon Cloth (NCO/ZCO/CC) including carbon cloth substrate, ZnCo2O4 nanosheets, and NiCo2O4 nanowires is prepared as a binder‐free anode for LIBs. Benefiting from the special hierarchical nanostructure and the synergistic interaction of the component, the as‐prepared NCO/ZCO/CC anode material exhibits good electrical conductivity, structural stability, and electrochemical kinetics, which can provide a high reversible areal capacity of 2.55 mAh cm−2 at 2 mA cm−2 after 200 cycles. At a high current density of 5 mA cm−2, the NCO/ZCO/CC electrode only takes about 20 min to fully charge and it can still reach a capacity of 1.50 mAh cm−2 with a capacity retention of 86.2% after 400 cycles, revealing the potential for fast charging at high rates. [ABSTRACT FROM AUTHOR]

Low electronic conductivity and large volume changes during the (de)lithiation process are the two main challenges for ZnO anode materials used for lithium‐ion batteries (LIB). Here, a free‐standing, flexible, and binder‐free LIB electrode composed of ZnO nanorods and carbon cloth (CC) is fabricated. This is then decorated with Ag nanoparticles and finally coated by an amorphous carbon layer to form the hybrid electrode: (C@(Ag&ZnO)). The voids among the nanorods are sufficient to accommodate the volume expansion of the ZnO while the flexible CC, which acts as the current collector, relieves the volume change‐induced stress. The Ag nanoparticles are effective in improving the conductivity. This composite electrode shows excellent LIB performance with a stable long cycling life over 500 cycles with a reversible capacity of 1093 mAh g−1 at a current density of 200 mA g−1. It also shows good rate performance with reversible capacity of 517 mAh g−1 under a high‐current density of 5000 mA g−1. In situ Raman spectroscopy is conducted to investigate the contributions of the amorphous carbon layer to the capacity of the whole electrode and the synergy between the CC and ZnO nanorods. [ABSTRACT FROM AUTHOR]

It is of particular significance to unveil the authentic coloration mechanism of the multivalent praseodymium colored ZrSiO4 yellow pigments for advanced decoration applications. We herein adopted a facile strategy to modulate the fluorine‐assisted zircon crystallization and thereby obtained ultrafine Pr‐ZrSiO4 yellow pigments, which have a remarkably narrow size distribution and average diameters within 250–400 nm. By virtue of some cogent combinative spectra of reflection, absorption, excitation, and emission from three types of elaborately‐designed H2‐, air‐, and O2‐based pigments, the coloration mechanism for the Pr‐colored zircon was systematically unveiled: both Pr4+ and Pr3+ coexist invariably in the pigments, while the former contributes primarily to the ligand‐to‐metal charge transfer from O2p to Pr(IV)4f for the blue–violet absorption to generate the yellow hue, and the latter is inclined to discolor the pigments. Therefore, an oxidizing atmosphere is preferable to produce brilliant Pr‐ZrSiO4 pigments with enhanced chromatic properties. The stark spectroscopic distinctions between the wide‐band absorption from the nonluminescent tetravalency and the narrow‐band absorption from the luminescent trivalency can expand our understanding to the rare‐earth‐based inorganic pigments. [ABSTRACT FROM AUTHOR]

The use of heterojunctions is a promising solution to the problem of cross‐sensitivity in gas sensors. In this work, a carbon monoxide sensor based on the CuO/TiO2 heterojunction was designed and fabricated. Due to the good adsorption properties of CuO materials to CO, and the heterojunction interface charge transfer, the CuO/TiO2 thin film sensor exhibits high sensitivity to CO at room temperature. The response is as high as 10.8–200 ppm CO, about 10 times its response to H2. Interference from H2 is greatly reduced by optimizing the structure of the CuO/TiO2 heterojunction. This reliable detection of carbon monoxide with excellent discrimination against H2 is of great significance for the development of CO gas sensors. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of insect resistance to toxic effects of phytochemicals can provide an insight into plant–herbivore interactions. Monochamus alternatus Hope, a main vector of pine wood nematode (Bursaphelenchus xylophilus), prefers to infest masson pine (Pinus massoniana Lamb) and causes huge economic and environmental losses. α‐Pinene is the primary component of resin produced by masson pine and plays a crucial role in defending against herbivorous insects, but its defensive effects on M. alternatus larvae are barely known. Here, we explored the physiological metabolism in M. alternatus larvae that were fumigated with (+)‐α‐pinene, (‐)‐α‐pinene, β‐pinene, (R)‐(+)‐limonene, myrcene and (‐)‐α‐phellandrene. (+)‐α‐Pinene showed the highest fumigant toxicity to M. alternatus larvae among these monoterpenes, and the fourth instar larvae possessed the highest resistance to this compound at the larval stage. Comparative transcriptome analysis detected 423 up‐regulated and 311 down‐regulated genes in the larvae fumigated with (+)‐α‐pinene, which were mainly related to detoxification, energy and protein metabolism. Among the differentially expressed genes encoding for detoxification enzymes, 14 P450s, 13 UGTs, 1GSTs and 3ABCs were dramatically up‐regulated in the larvae fumigated with (+)‐α‐pinene. Silencing of P450s via RNA interference led to an increased mortality in the larval fumigated with (+)‐α‐pinene. Piperonyl butoxide exposure significantly increased the mortality and inhibited the expressions of P450s, UGTs and ABCs in the larvae fumigated with (+)‐α‐pinene. These results suggested an important role of P450s in the resistance of M. alternatus larvae to (+)‐α‐pinene fumigation, which may facilitate the understanding of terpenoid detoxification in M. alternatus larvae. [ABSTRACT FROM AUTHOR]

Zircon has been widely applied in various traditional and emerging fields due to its distinct physiochemical advantages while monodisperse spherical zircon (MSZ) powders hitherto have not been explored for the tremendous challenges in the control of zircon crystallization and growth. Herein, systematic investigations are presented to reveal the paramount role of halide mineralizers upon the crystallization and growth of MSZ powders synthesized under highly acidic hydrothermal environments (pH <0). A formation mechanism is revealed revolving around the complexation of central Zr4+ with the Lewis basic ligand, fluorine, which forms the F‐containing species of [(OH)1–y·Ry] (R = F, Cl) to replace Zr and generates Zr‐deficient zircons as (ZrO4)1‐xSi[(OH)1‐y·Ry]4x. This finding differs much from conventional views on common fluoro‐hydroxylated hydrothermal zircons, which were generally regarded as Si‐deficient silicates from the substitution of fluoro‐hydroxyls for the [SiO4] tetrahedra. A parameter, Kr=4xy, is first proposed as an index to evaluate the stability of hydrothermal zircons. The MSZ powders demonstrate superb thermal stability at high temperature, superior photo‐reflectance, and thermal insulation over normal zircons, promising attractive prospects to extend zircon applications. [ABSTRACT FROM AUTHOR]

Fullerene (C60) nanowires have attracted significant attention in the past two decades due to their outstanding chemical and physical properties, which render the material a wide range of potential applications. Much effort has been devoted to exploring the growth methods, structural and compositional characterizations, and application‐related investigations of this novel carbon nanomaterial. Here, we present a review of C60 nanowires in which we will first describe the recent development in the material preparations, analytical techniques, crystal structures, chemical compositions, and the investigations of polymerization processes. Afterward, we will discuss the mechanistic studies on the nanowires' growth as the mechanism research is of great importance for their size control, large‐scale preparation, and for the exploration of applications in a wide range of fields. Finally, we will discuss the potential applications in several directions, including optical, electrical, mechanical, and biological fields, as well as our perspectives to future developments. [ABSTRACT FROM AUTHOR]

Atherosclerosis is regarded as a chronic progressive inflammatory disease and is a basic pathophysiological process in coronary artery disease which is life threatening in clinic. The formation of foam cell plays a key role in the pathogenesis of atherosclerosis. OxLDL is a significant factor in progression of coronary artery disease. Our studies have demonstrated that USP14 promotes cancer development and mediates progression of cardiac hypertrophy and LPS‐induced inflammation. However, the underlying mechanism of USP14 is unknown. In this study, we found that the inhibition of USP14 significantly suppressed the oxLDL uptake, subsequently decreased the foam cell formation. Surprisingly, USP14 has an effect on the expression of CD36 but not SR‐A, ABCA1, Lox‐1, ABCG1 and SR‐Bl. Furthermore, USP14 stabilizes CD36 protein via cleaving the ubiquitin chain on CD36. Blocking CD36 activation using antibody‐dependent blocking assay remarkably attenuated the function of USP14 on the formation of foam cell. In summary, our results suggested that the inhibition of USP14 decreases foam cell formation by down‐regulating CD36‐mediated lipid uptake and provides a potential therapeutic target for atherosclerosis. [ABSTRACT FROM AUTHOR]

Dendritic MoO3/Ag with good crystallinity has been prepared through an operando method. In the hydrogen evolution reaction (HER), this catalyst, which was designed to utilize the best properties of each component material, showed a high catalytic activity. After the precursor was drop-cast onto a glassy carbon electrode, a reductive potential was applied to the coated electrode, and H2 evolution occurred within the range of potentials. The overpotential required to evolve H2 at the benchmark rate decreased progressively with subsequent voltammetric cycles, until a steady state was reached at which only 145 mV of overpotential was required to pass −10 mA cm−2 of current density. During the electrocatalysis, the precursor was converted to catalyst through an operando method. This operando-synthesized MoO3/Ag catalyst has a low Tafel slope (43 mV dec−1), low overpotential (145 mV), and excellent durability for HER. It has the potential to be a promising material for HER. [ABSTRACT FROM AUTHOR]