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Electrospun nanofibers (NFs) have shown excellent properties including high porosity, abundant active sites, controllable diameter, uniform and designable structure, high mechanical strength, and superior resistance to external destruction, which are ideal nanoreactors for in situ characterizations. Among various techniques, in situ transmission electron microscopy (TEM) has enabled operando observation at the atomic level due to its high temporal and spatial resolution combined with excellent sensitivity, which is of great importance for rational materials design and performance improvement. In this review, the basic knowledge of in situ TEM techniques and the advantages of electrospun nanoreactors for in situ TEM characterization are first introduced. The recent development in electrospun nanoreactors for studying the physical properties, structural evolution, phase transition, and formation mechanisms of materials using in situ TEM is then summarized. The electrochemical behaviors of carbon nanofibers (CNFs), metal/metal oxide NFs, and solid‐electrolyte interphase for different rechargeable batteries are highlighted. Finally, challenges faced by electrospun nanoreactors for in situ TEM characterization are discussed and potential solutions are proposed to advance this field. [ABSTRACT FROM AUTHOR]

Sulfurized polyacrylonitrile (SPAN) has attracted considerable interest for high-energy lithium–sulfur batteries owing to its high specific capacity and remarkable cyclic stability. However, common electrolytes fail to stabilize both the lithium (Li) metal anode and SPAN cathode, thus affecting their practical applications. Herein, a lightweight siloxane solvent-based electrolyte (below 1 g mL−1) comprising 1.5 M lithium bis(fluorosuflonyl) imide (LiFSI) in dimethyldimethoxysilane (DMMS) has been designed for linking metallic Li and high-capacity SPAN cathode simultaneously. The weakly solvating DMMS electrolyte with a moderate salt concentration of 1.5 M not only allows a remarkable Li stripping/plating CE of 99.6% but also retards the dissolution of polysulfides. As a result, the assembled Li‖SPAN cells delivered a superior cyclic stability of 513 mA h g−1 at 0.2 A g−1 with 96.9% capacity retention after 300 cycles. Depth-profiling X-ray photoelectron spectroscopy results confirm the generation of an inorganic-rich inner layer in electrode–electrolyte interphases with trace DMMS decomposition in the outer layer, thus enabling uniform Li deposition. Density functional theory result suggests weak affinity between the DMMS solvent and polysulfides, which minimizes polysulfide shuttling. This study provides a new avenue to explore novel solvents to simultaneously stabilize metallic Li and SPAN cathodes. [ABSTRACT FROM AUTHOR]

Rechargeable potassium (K) batteries that are of low cost, with high energy densities and long cycle lives have attracted tremendous interest in affordable and large-scale energy storage. However, the large size of the K-ion leads to sluggish reaction kinetics and causes a large volume variation during the ion insertion/extraction processes, thus hindering the utilization of active electrode materials, triggering a serious structural collapse, and deteriorating the cycling performance. Therefore, the exploration of suitable materials/hosts that can reversibly and sustainably accommodate K-ions and host K metals are urgently needed. Electrospun carbon-based materials have been extensively studied as electrode/host materials for rechargeable K batteries owing to their designable structures, tunable composition, hierarchical pores, high conductivity, large surface areas, and good flexibility. Here, we present the recent developments in electrospun CNF-based nanomaterials for various K batteries (e.g., K-ion batteries, K metal batteries, K–chalcogen batteries), including their fabrication methods, structural modulation, and electrochemical performance. This Feature Article is expected to offer guidelines for the rational design of novel electrospun electrodes for the next-generation K batteries. [ABSTRACT FROM AUTHOR]

Electronic devices with rectifying effect are typical building blocks for integrated circuits and useful for photodetectors. Herein, a new type of diode based on plasmonic tunnel hetero‐nanostructure is reported. By constructing a planar plasmoelectric junction between p‐Si and Au pad electrode with a few‐layer‐stacked 2D plasmonic AuNP‐nanomembrane as a medium layer, rectifying behavior of the device is achieved, though the direct contact between bulk Au and semiconductor usually tends to form ohmic contact. The electrically driven plasmons enable the 2D AuNP‐nanomembrane to be electron‐rich, while the asymmetric band alignment which causes bidirectionally different barrier at the (buried) interface results in the unidirectional rectifying behavior of the constructed plasmonic diode (p‐diode). The planar junction made of shell‐isolated Au@SiO2 NP‐nanomembrane (instead of AuNP‐nanomembrane) shows still rectifying behaviors but better photoresponse, due to structurally well‐defined/ordered nanostructures and intensified plasmonic tunneling effect of the nanomembrane. The as‐constructed p‐diode‐based photodetector with Au@SiO2 NP‐nanomembrane shows impressive photoresponse with a high photoresponsivity value of 6.496 A W‐1 and a detectivity value of 1.9859 × 1011 Jones under the 268 µW cm‐2 650 nm laser irradiance, comparable to the reported values of similar devices prepared from other 2D materials. [ABSTRACT FROM AUTHOR]

Shell‐isolated nanostructures, consisting of an inert shell and a plasmonic core, have recently been intensively explored for biosensing, catalysis, and nanoelectronics applications owing to their functional shells and unique plasmonic properties. Such designer shell‐isolated plasmonic nanostructures possess the potential to improve the detectability of biosensors and provide powerful platforms to explore in‐depth plasmon enhancement principles and finally boost significantly their photo(electro)catalytic efficiency. In addition, such structural optimization and interface nanoengineering promote solid developments of advanced nanoelectronics toward real applications, revealing new electron transport mechanisms and enabling exploration of new functional and integrated optoelectronic devices. In this overview, the state‐of‐the‐art progresses of shell‐isolated plasmonic nanostructures (SHIPNSs) in the field of biosensing, photo(electro)catalysis, and nanoelectronics is summarized, focusing on the superiority of the core–shell materials in exploration of biosensing, catalytic enhancement mechanisms, and electron transport principles. A brief overview of synthetic methods is introduced, and then the significant importance of shell‐isolated nanomaterials in fabrication and promising direction for future development and challenges are discussed. [ABSTRACT FROM AUTHOR]

Objective. The current study sought to compare the effects of the addition of Qingshen granules to conventional Western medicine on immune function in patients with comorbid chronic renal failure and damp-heat syndrome and to explore the possible mechanisms responsible for any differences observed. Methods. Through a multicenter, randomized, controlled study, a total of 282 eligible patients were divided into experimental (n = 136) and control groups (n = 146). All of the patients were treated with conventional Western medical therapy. The experimental group also received Qingshen granules three times daily for 12 weeks. Clinical efficacy was observed in the two groups. Peripheral blood levels of CD4+ T cells, CD8+ T cells, Th17 cells, nuclear factor-κB p65 (NF-κB p65) activity, serum interleukin-17 (IL-17), serum interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor-associated factor 6 (TRAF6), fibronectin (FN), and type IV collagen (Col-IV) were detected in both groups. Results. The total clinical curative effective rate was significantly higher p < 0.05 in the experimental group (79.41%) than in the control group (67.12%). Before treatment, there were no significant differences in CD4+/CD8+ T cell ratio, Th17 cell level, NF-κB p65 activity, serum IL-17, IL-6, TNF-α, TRAF6, FN, and Col-IV between the experimental and control groups p > 0.05 ; however, all of the measures were significantly higher than those observed in a healthy comparison group (p < 0.05 or p < 0.01). After treatment, the above indexes in the experimental group were significantly lower than those before treatment (p < 0.05 or p < 0.01). Similarly, NF-κB p65 activity, serum IL-17, TNF-α, TRAF6, FN, and Col-IV in the control group were significantly lower than the levels observed prior to treatment (p < 0.05 or p < 0.01); however, while all of the other indexes were lower than those observed before treatment, the differences were not statistically significant p > 0.05 . Conclusion. Qingshen granules adjust immune dysfunction, improve immunity mediated inflammatory response, and attenuate renal fibrosis in patients with comorbid chronic renal failure and damp-heat syndrome. [ABSTRACT FROM AUTHOR]

Bacteriorhodopsin (bR), a proton-pumping protein that converts light into electrochemical energy, has recently attracted attention for solar energy conversion applications. However, its application for electrochemical supercapacitors has not been reported due to the demanding requirements on ordered oriented membranes. Herein, the authors explore bR for supercapacitor application by decorating oriented bR-monolayers onto the surface of an ordered and highly capacitive polyaniline (PANI)-nanofilm prepared by electropolymerization on an Au electrode. The prepared PANI-nanofilm displays good and tunable pseudocapacitive performance attributed to its multiple proton doping states. Due to the synergistic contribution of light-induced proton pumping capacity and the photoelectric function of bR, the specific capacitance of the bR/PANI/Au-electrode has been enhanced pronouncedly by the introduction of oriented bR-monolayers, and has been further improved upon light irradiation. At a current density of 60 A g−1, a specific capacitance as high as 1146 F g−1 was achieved following 550 nm light irradiation for the as-prepared bR/PANI-nanocomposites. [ABSTRACT FROM AUTHOR]

Due to the ability to harness surface plasmons to promote solar‐to‐chemical energy conversion, plasmonic nanoparticles with finely‐controlled structure and optical properties hold great promise for light‐activated catalysis. Herein, we prepared a strong plasmonic nanostructure, by assembling Pd/Ag nanosheets (NSs) with varied Pd/Ag ratio onto the surface of polystyrene (PS) microsphere to form a spherical nanoassembly (NAs). The as‐prepared Pd/Ag‐PS NAs showed better photothermal performance than the precursor Pd/Ag NSs of the same concentration. More importantly, the as‐prepared Pd/Ag‐PS NAs can be used to boost light‐driven organic hydrogenation reactions, in which Pd nanocomponent acts as hydrogenation reaction active sites and Pd/Ag‐NSs can convert light efficiently into heat. Under room temperature conditions, the light‐driven catalytic hydrogenation efficiency under 50 mW/cm2 full‐spectrum irradiation proved to be comparable to that of thermally (70 °C) driven reactions. Moreover, the as‐prepared Pd/Ag‐PS NAs has better photostability than Pd/Ag NSs. The results proved that the photothermal effect rather than the transfer of hot electrons is responsible for enhanced photocatalytic hydrogenation performance. The strong plasmon coupling between closely‐packed Pd/Ag NSs enhances the electromagnetic field intensity and scattering intensity and increase Vis‐NIR light trapping and high density hot spots generation, which lead to an overall better photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

An electrode-supported hetero-nanostructured CoNi@C–Au/TiO2 catalyst was prepared and used for electrocatalytic full water splitting. Plasmon-enhanced electrocatalytic H2 and O2 generation under visible light irradiation (λ > 420 nm) was demonstrated. HER overpotentials of 98 and 445 mV to drive current densities of 1 and 10 mA cm−2, respectively, were achieved, while the OER photocurrent at 0 V reached 3.4 mA cm−2 under solar illumination (λ > 420 nm, 100 mW cm−2) in a 0.01 M KOH aqueous solution. [ABSTRACT FROM AUTHOR]

This letter proposes a novel wirelessly-powered full-duplex amplify-and-forward (AF) relaying scheme, where the multi-antenna relay can harvest energy from the source and recycle energy from itself by using antenna switching protocol. Unlike conventional fixed antennas relay that can only harvest and recycle energy at the second transmission phase, in the proposed scheme, the relay can also harvest energy at the first transmission phase with dynamic antenna combination. To maximize the spectral efficiency of the system, the transmit power of the source, the beamforming matrix at the relay and its antenna allocation are jointly optimized. Also, to tackle the discontinuity and nonconvexity of the optimization problem, a semi-analytical iterative algorithm is developed. In particular, for a fixed antenna combination at the relay, a closed-form solution to the source power allocation and the beamforming matrix at the relay are derived. Then, a greedy antenna switching algorithm is designed to obtain the best antenna combination. Simulation results demonstrate the near optimality of the proposed algorithm and the superiority of the proposed scheme. [ABSTRACT FROM AUTHOR]

A ternary Pt/Au/TiO2 nanoparticle (NP) decorated plasmonic wood carbon has been successfully fabricated by a simple two‐step calcination method. The as‐prepared Pt/Au/TiO2 NP‐decorated wood carbon showed an interfacial solar steam generation efficiency up to 90.4 %. Furthermore, the floating system exhibits an excellent photodegradation of tetracycline (TC; 40 mg L−1). Up to 94 % degradation was achieved after 80 min of continuous light irradiation (λ>420 nm) with the assistance of solar steam process. The photocatalysis is promoted by the introduction of Pt/Au nanocomponents, which suppress the recombination of electron–hole pairs generated on TiO2 and facilitate electron transfer. High‐performance liquid chromatography mass spectrometry was employed to identify the reaction products of the photocatalytic system and a mechanistic insight was also provided. The as‐prepared three‐dimensional plasmonic wood carbon has a high photocatalytic performance. Such wood carbon‐based system is recyclable and scalable for practical and versatile solar‐driven clean water generation. Killing two birds with one wooden block: A ternary Pt/Au/TiO2 decorated plasmonic wood‐carbon‐based floating device was explored for photodegradation of tetracycline (TC). The effective solar steam evaporation capability benefits the contact and mass transfer of contaminants to the catalysts. Further, plasmonic effect of Pt/Au nanoparticles promotes charge separation over TiO2. A high photodegradation rate of TC was achieved under visible‐light irradiation. [ABSTRACT FROM AUTHOR]

The search for a low‐cost, noble‐metal‐free cocatalyst to replace expensive Pt for hydrogen (H2) photogeneration in water has become a hot research topic, and among these, Ni‐based cocatalysts are promising and highly desired. Developing new strategies and protocols to obtain Ni‐based cocatalysts with high activity is therefore vitally important. Herein, we develop a new method to efficiently decorate divalent Ni onto pre‐synthesized CdS/CdSe core/shell quantum dots (QDs). The concentration of Ni on the QDs can be easily tuned by varying the amount of the Ni precursor introduced during the synthesis. Further analyses reveal that Ni2+ can be strongly decorated onto QDs. Impressively, the Ni‐decorated QDs displayed a significantly enhanced H2 photogeneration performance as compared to the two components prepared separately. Through the optimization of the Ni concentration on the QDs, the turnover frequency (TOF) with respect to Ni and quantum yield (ΦH2) at 520 nm for H2 evolution from water could reach 322 h−1 and 12.3 %, respectively. A possible mechanism has also been proposed and discussed in detail. Divalent nickel can be decorated onto CdS/CdSe core/shell quantum dots (QDs) in a controlled fashion. Under optimized conditions these QDs catalyze light‐induced H2 evolution from water with a turnover frequency of 322 h−1 with respect to Ni and a quantum yield of 12.3 % at 520 nm. [ABSTRACT FROM AUTHOR]

Engineering sensitive gold-based nanostructured “ultra-microelectrode” systems have been an essential part of As(iii) sensing due to their high theoretical efficiency, high oxygen overpotential, high abundance and environmental benignity. However, it is still challenging to increase the specific active sites and enhance the electrocatalytic activity, the lack of which significantly limits the overall As(iii) sensing performance and largely prevent its utilization in ultra-trace detection of As(iii) in practical water systems. Herein, we report a detailed design of adsorbent assisted Fe oxide-based plasmonic Ag/Au hollow and porous nanoshells (Ag/Au HPNSs@FO) for electrochemical As(iii) determination and ultra-trace detection of As(iii) in practical water systems based on the integrated advantages of the plasmonic and ultra-microelectrode nanostructure. Ag nanoparticles were used merely as starting templates for the fabrication of plasmonic Ag/Au HPNSs and then, porous Fe oxide, with good adsorption capacity toward As(iii), was introduced by pyrolysis treatment of MIL-100(Fe) grown on the Ag/Au HPNSs. The remarkable features of abundant micro-reactive sites, improved electrochemical activity, and synergistic effects have vastly ensured outstanding electrocatalytical performance of the arsenic redox reaction. The wide linear range of detection is from 0.05 to 16 ppb and the detection limit (3σ) is 0.01 ppb. Moreover, Ag/Au HPNSs@FO exhibits high sensitivity (922.5 μA ppb−1) and stable detection. Most importantly, the ultra-trace detection of As(iii) in practical water systems can be achieved by Ag/Au HPNSs@FO with unprecedentedly low concentrations (ca. 1 ppt and even lower concentrations). [ABSTRACT FROM AUTHOR]