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Maintaining a consistently high current density growth rate in the hydrogen evolution reaction is highly challenging because the limited mass transfer rate at the electrode/electrolyte interface will make the adsorption reaction as the rate‐determining step associated with a low hydrogen coverage, exhibiting a Tafel slope >120 mV dec–1. Therefore, maximizing the current density range in which the desorption reaction is the rate‐determining step, can significantly reduce the overpotential. Herein, a surface sulfur decoration strategy is presented to modify the molybdenum carbide electrocatalyst and achieve coordinated adsorption/desorption kinetics, leading to a dominant Volmer–Heyrovsky mechanism across a wide range of current densities. Both experimental and theoretical results validate the surface charge redistribution induced by sulfur decoration, which subtly optimizes the Gibbs free energy of hydrogen adsorption and enhances the in‐plane polarization field. As a result, the as‐obtained surface sulfur‐decorated molybdenum carbide electrocatalyst exhibits coordinated adsorption/desorption kinetics and efficient hydrogen delivery, ultimately surpassing the commercial Pt/C electrocatalyst for high‐efficiency hydrogen evolution. [ABSTRACT FROM AUTHOR]

Surface decoration of support structures by physical vapor deposition (PVD) of small molecular building blocks offers a versatile platform to realize functional supramolecular nanofibers in a controlled manner and with tailored properties. Here, details on the preparation of surface‐decorated polyamide fabrics by PVD using N1,N3,N5‐tris[2‐(diisopropylamino)‐ethyl]‐1,3,5‐benzenetricarboxamide (1) as a molecular building block are reported. It is shown that a defined morphology with uniform nanofiber length can be achieved, which is controlled by the PVD conditions. The functional periphery of supramolecular nanofibers of 1 allows the immobilization of gold nanoparticles (AuNPs). This results in AuNP‐loaded nanostructures with a high surface area, which can be used as a heterogenous catalyst for the reduction of 4‐nitrophenol in aqueous media. The surface‐decorated support structures with firmly deposited AuNPs also provide the opportunity to conveniently reuse these structures without compromising the catalytic performance. This approach provides fabrication strategies for the controlled surface decoration of macroscopic support structures with small molecular building blocks by PVD with the potential to realize functional robust supramolecular nanofibers for various catalytic or filtration applications. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) show great prospects in large‐scale energy storage applications, whereas this technology suffers from the lack of cathode materials with high capacity and stability. Here, a cathode material of SbO2 nanoparticles decorated onto the surface of K0.43V6O13 nanobelt is presented. The SbO2 is disclosed as proton‐phile and zinc‐phobic, which thus favors H+ intercalation. In consequence, the increase of H+ intercalation can offset the lattice shrinkage caused by Zn2+ intercalation, and contribute to excellent cyclic stability of the battery. Finally, SbO2/K0.43V6O13 delivers a reversible capacity of 414.2 mAh g−1 at 1 A g−1 after 1000 cycles with a retention of 103%, and 223.5 mAh g−1 at 20 A g−1 after 20 000 cycles with a retention of 89.3%, showing long cycling life at both low current and high current densities. This study provides new insights into the effecting factors for the performance of AZIBs cathode and an effective strategy to improve its stability. [ABSTRACT FROM AUTHOR]

A Cu‐based supported catalyst with g‐C3N4 coating (Cu/g‐C3N4@AC) was prepared by facile in‐situ growth over activated carbon surface with urea and Cu(NO3)2, and the catalytic performance for wet air oxidation of phenolic wastewater was investigated. The effects of different reaction conditions (catalyst, temperature, pressure and pH) were examined. The results show that under the catalysis of Cu/g‐C3N4@AC phenol could be completely oxidized at 120 °C and 0.5 MPa O2 with COD removal of 92.6 % (from 4883 mg/L to 361 mg/L). TEM, BET, XRD, FTIR and XPS characterizations showed that g‐C3N4 coating could strengthen the metal surface interaction via the Cu−N−C bonds formation, thus suppressing the aggregation of the active components on the surface and mitigating the catalyst deactivation. Moreover, the interaction between the Cu species and the g‐C3N4 structure facilitates the electron transfer and thus significantly boost up the catalytic activity. These findings help explore efficient catalysts for the wastewater treatment via wet air oxidation under mild conditions. [ABSTRACT FROM AUTHOR]

Underwater optical communication (UOC) has attracted considerable interest in the continuous expansion of human activities in marine/ocean environments. The water‐durable and self‐powered photoelectrodes that act as a battery‐free light receiver in UOC are particularly crucial, as they may directly face complex underwater conditions. Emerging photoelectrochemical (PEC)‐type photodetectors are appealing owing to their intrinsic aqueous operation characteristics with versatile tunability of photoresponses. Herein, a self‐powered PEC photodetector employing n‐type gallium nitride (GaN) nanowires as a photoelectrode, which is decorated with an iridium oxide (IrOx) layer to optimize charge transfer dynamics at the GaN/electrolyte interface, is reported. Strikingly, the constructed n‐GaN/IrOx photoelectrode breaks the responsivity‐bandwidth trade‐off limit by simultaneously improving the response speed and responsivity, delivering an ultrafast response speed with response/recovery times of only 2 µs/4 µs while achieving a high responsivity of 110.1 mA W−1. Importantly, the device exhibits a large bandwidth with 3 dB cutoff frequency exceeding 100 kHz in UOC tests, which is one of the highest values among self‐powered photodetectors employed in optical communication system. [ABSTRACT FROM AUTHOR]

Electrical explosion, characterized by ultrafast atomization and quenching rate (dT/dt ≈ 1010–1012 K s–1) of the sample, is a unique approach for "one‐step" synthesis of nanomaterials. Experiments are carried out with layered graphite and Bi2Se3 under the action of electrical explosion in a confined reaction tube. High‐speed photography and electrophysical diagnostics are applied to characterize dynamic processes. SEM and EDS are used to characterize surface micro‐morphology of reaction products. The layered materials are first exfoliated to thin nanosheets/nanocrystals by shock waves and turbulent flow of the explosion. As the ionized explosion products (>10 000 K) contacts the sample, intense heat transfer happens, simultaneously atomizing the sample and quenching the plasmas. As a result, nanoparticles grow on the surface of thin sheets, forming "dot‐sheet" structure. The size distribution of the nanoparticles typically ranges from 10 to 100 nm, following Log‐normal distribution. The dotted graphite nanosheets gather together and form a stacked/cabbage‐like structure. By contrast, Bi2Se3 case accompanies with chemical reactions, causing surface corrosion and showing more possibilities: nanocrystals and nanotubes growth on different areas of the sample. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC), affecting millions of patients worldwide, is associated with disorders of the gut microbiota. Probiotics‐based therapy positively regulating the community structure of gut microbiota is regarded as an efficient intervention for UC. However, oral probiotics delivery is restricted by limited bioactivity, short retention time, complex pathological condition, and single therapeutic efficacy. Here, a bioengineered probiotic decorated with a multifunctional prodrug coating is constructed to ameliorate the aforementioned shortcomings. The results of UC mice induced by dextran sulfate sodium demonstrate that the intrinsic features of the fabricated coating integrate gut microbes protection, colon‐targeted drug release, prolonged drug retention, and inflammation regulation. In parallel, the probiotics Lactobacillus rhamnosus GG (LGG) could regulate the composition of the gut microbiota and improve epithelial barrier function, thereby synergistically ameliorating UC. These results provide ample shreds of evidence of the therapeutic effect on UC, therefore, demonstrate a great promise as the potential therapeutic strategy for UC treatment. [ABSTRACT FROM AUTHOR]

In this paper, the nest‐like Zn layers on the surface of short carbon fibers (CFs) was obtained by electrodeposition technique to improve the mechanical properties of rigid polyurethane (RPU) composites. The scanning electron microscopy (SEM) showed that the desired nest‐like Zn crystals were successfully deposited on the surface of CFs. The X‐ray powder diffractometer (XRD) and contact angle instrument were used to analyze the crystal composition of the layers and the wettability of fiber surface. Compared with pristine short carbon fibers/rigid polyurethane (CFs‐RPU) composites, the tensile strength, bending strength, impact strength and interlaminar shear strength (ILSS) of nest‐like Zn layers decorated short carbon fibers/rigid polyurethane (NS‐CFs/RPU) composites were improved simultaneously. Dynamic mechanical test (DMA) results showed that the nest‐like Zn layers on the surface of CFs effectively improved the interfacial bonding strength between CFs and the RPU matrix. In addition, the cross‐section of NS‐CFs/RPU composites showed the metal layer combines well with the matrix. The above results indicated that the improvement of strength and toughness of NS‐CFs/RPU composites was attributed to the pinning effect of the nest‐like Zn layers on the surface of carbon fiber and the increased of crack propagation path. [ABSTRACT FROM AUTHOR]

Powdered Au‐nanoparticle‐modified ZnO (ZnO–Au) nanocomposites having high photocatalytic activity are synthesized via a simple, facile, and controlled method. Through hydrothermal reactions, ZnO nanorods are first grown and the rod surface is then decorated with Au nanoparticles, with the number of Au nanoparticles being adjustable by changing the concentration of tetrachloroauric acid (HAuCl4) in the precursor hydrothermal solution. The ZnO nanorods have an average length of 2 μm and diameter of 300 nm, and the Au nanoparticles are nearly spherical sized between 5 and 10 nm. The ZnO–Au nanocomposites have a higher light absorption capacity and lower carrier recombination rate than the bare ZnO nanorods, which is attributed to the plasmonic sensitizing of Au nanoparticles and makes the synthesized ZnO–Au nanocomposites photocatalytically active. The photocatalytic activity of the ZnO–Au nanocomposites is investigated by degrading rhodamine B (RhB) under visible light illumination, demonstrating that RhB can be photocatalytically degraded more efficiently with the ZnO–Au nanocomposites than with the bare ZnO nanorods, with the rate constant increasing from 6.36 × 10−4 min−1 for the bare ZnO nanorods to 1.19 × 10−2 min−1 for the ZnO–Au nanocomposites. The ZnO–Au nanocomposites also exhibit good photocatalytic stability and can be reused as photocatalysts. [ABSTRACT FROM AUTHOR]

The intriguing surface sensitivity of the single‐crystalline semiconductor nanowires offers tremendous opportunity in tuning the physical properties of nanophotonic and nanoelectronic devices for versatile applications. Particularly, in the pursuit of emerging photoelectrochemical (PEC)‐type devices, significant efforts have been devoted to understanding the charge transfer dynamics between the nanowires and the electrolyte. Here, a PEC‐type ultraviolet photodetector consisting of GaN p‐n junction nanowires as photoelectrodes is constructed. It is found that two competing charge transport processes at the nanowires' surface as well as in the p‐n junction co‐determine the photoresponsive behavior of the device. Furthermore, the surface platinum (Pt) decoration has successfully tuned the charge transfer dynamics by enhancing the charge transport efficiency at the surface, resulting in a twenty‐fold increase of the photocurrent compared to the pristine GaN nanowires. Theoretical calculations reveal that the newly formed electronic states at the Pt/GaN interface account for the improved charge transfer at the surface, and the optimal hydrogen adsorption energy contributes to the boosted PEC reaction rate. The synergy of these two effects uncover the underlying mechanism of the high photoresponse of the constructed Pt/GaN‐nanowires‐based PEC photodetectors. [ABSTRACT FROM AUTHOR]

In this study, the decoration of nanostructured sorbent on polyacrylonitrile electrospun nanofibers, as a novel modification method was used for fabricating sportive thin films. Zeolitic imidazolate frameworks were directly grown on the surface of polyacrylonitrile nanofibers and for the first time applied for thin‐film solid‐phase microextraction of fluoxetine. The extraction efficiency of the novel thin film was compared with that of electrospun nanofibers modified with a common method of doping nanoparticles into nanofibers. The decorated nanofibers revealed 30 times higher surface area and four times higher extraction efficiency than doped nanofibers for the extraction of fluoxetine. The effective parameters on the efficiency of fluoxetine extraction and desorption were optimized using one factor‐at‐a‐time method. Under the optimum condition, limits of detection and quantification were 0.5 and 2 ng/mL, respectively. The linear dynamic range of the developed method was 2–2500 ng/mL (R2 = 0.997). The relative standard deviation of the method was <14.2%. The absolute recovery was 45%, while the relative recoveries were 77.3–97.5%. The developed method was an easy, simple, and sensitive method for the determination of fluoxetine in the environmental and biological samples. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOF) materials are promising materials for gas separation, but their application still faces various challenges. A strategy is now reported for introducing subunits of MOFs into traditional zeolite frameworks to obtain applicable adsorbents with advantages of both zeolites and MOFs. The subunits of ZIFs were introduced into zeolite Y and zeolite ZSM‐5 for CH4/N2 separation. Both the molecular simulation and experimental results validated that the IAST CH4/N2 selectivity of the resulting samples greatly improved (above 8, at 100 kPa and 25 °C) with the incorporation of ZIF subunits into zeolites structure, and the selectivities were obviously higher than that of zeolites and even better than that of ZIFs. This strategy not only gave rise to an efficient adsorbent for CH4/N2 separation but also provided ideas for design of other adsorption and separation materials. [ABSTRACT FROM AUTHOR]

Recently, III-V semiconductor nanowires (NWs) are widely investigated as field-effect transistors (FETs) for high-performance electronics, optoelectronic, and others; nevertheless, effective control in their device performances, especially the threshold voltage is still not well attained, which can potentially limit their practical uses for technological applications. This study reports a simple but highly reliable metal-oxide nanoparticle (NP) surface decoration approach onto the device channel in order to manipulate electrical characteristics of III-V NWFETs, such as the threshold voltage and transistor operation, through the manipulation of free electrons in the NW channel (i.e., InAs, InP, and In0.7Ga0.3As) via depositing various metal-oxide NPs with different work functions. Without any passivation layer, this decoration approach can yield the stable NW device characteristics in ambient. Notably, the versatility of our decoration scheme has also been illustrated through the realization of highperformance enhancement-mode InAs NW-paralleled-arrayed devices as well as the configuration of highly efficient InAs NW NMOS inverters, comprising of both depletion and enhancement mode devices. All these results further elucidate the technological potential of this decoration approach for future high-performance, low-power nanoelectronic device fabrication, and circuit integration. [ABSTRACT FROM AUTHOR]

The design and exploration of the transition metal oxides (TMOs)–carbon composite are greatly desired for enhanced supercapacitor application due to the low hydrophilicity and electrical conductivity of the prime TMOs. In this work, the highly hydrophilic carbon dots (CDs) with an average size of 2.56 nm are synthesized by a microwave thermolysis method, and then used as a decoration agent on the surface of NiCo2O4 nanowires. The CDs‐decorated NiCo2O4 (CDs/NiCo2O4) with a high surface area of 120.0 m2 g−1 is prepared via a one‐pot hydrothermal method and subsequent annealing. Only a small amount of CDs' decoration not only makes the surface more hydrophilic and easier for aqueous electrolyte infiltration into electrode, but can also promote the electrical conductivity of the as‐synthesized CDs/NiCo2O4 to 30‐fold higher than the prime NiCo2O4, and greatly decrease the internal resistance of the electrode material. Therefore, the CDs/NiCo2O4‐based three‐electrode system shows an extremely high specific capacitance (2202 F g−1) while a symmetrical CDs/NiCo2O4 supercapacitor offers a desirable energy density up to 73.5 Wh kg−1. This work provides a new strategy to improve supercapacitance as well as energy density of TMO‐based electrodes via a convenient surface decoration method by using carbon nanomaterials. [ABSTRACT FROM AUTHOR]

The development of high‐performance electrochemical energy storage and conversion technologies hinges largely on the creation of highly efficient and durable electrode materials. For many promising perovskite‐based electrode materials, however, nanosized islands of inert or insulating oxides, induced by cation segregation, are often formed on the surfaces under operating conditions, which severely degrade the electrocatalytic activity and long‐term stability. Here, the findings in effectively mitigating the challenges by controlling localized surface chemical states via surface decoration are reported. It is found that addition of SrO at La0.6Sr0.4CoO3−δ surface can induce self‐assembly of highly active perovskite coatings, avoiding the formation of inactive islands. Such coatings are found to act as active centers providing more than 10 times higher localized conductivity than the segregated islands and twice faster oxygen exchange kinetics than the perovskite surfaces, resulting in nearly 30 times improvement in electrochemical performances at 600 °C. The findings provide a novel approach to rational design and modification of perovskite electrode surfaces for higher and more durable electrochemical performance. Surface decoration of perovskite La0.6Sr0.4CoO3−δ electrodes by Sr ions through solution infiltration is found to enhance the oxygen reduction reaction activities at 600 °C by ≈30 times, attributed mainly to the in situ self‐assembly of highly active perovskite coatings induced by extrinsic Sr ions. [ABSTRACT FROM AUTHOR]