Development of novel bioanalytical methods for monitoring of H2S is key toward understanding the physiological and pathological functions of this gasotransmitter in live organisms. A ...ruthenium(II)‐complex‐based luminescence probe, Ru‐MDB (MDB: 4’‐methyl‐2,2’‐bipyridine‐4‐yl)methyl 2‐((2,4‐dinitrophenyl)thio)benzoate), was developed by introducing a new H2S responsive masking moiety to a red‐emitting RuII luminophore. Cleavage of this masking group by a H2S‐triggered reaction leads to a luminescence “off–on” response. The long‐lived emissions of Ru‐MDB and its reaction product with H2S allowed quantitative detection of H2S in autofluorescence‐rich human sera and adult zebrafish organs using the time‐gated luminescence mode. Ru‐MDB exhibits red emission, a large Stokes shift, high specificity and sensitivity for H2S detection, and low cytotoxicity, which enables imaging and flow cytometry analysis of lysosomal H2S generation in live inflamed cells under drug stimulation. Monitoring of H2S in live Daphnia magna, zebrafish embryos, adult zebrafish, and mice, was conducted by in vivo imaging using Ru‐MDB as a probe.
In vivo sensing of H2S: A luminescent probe, Ru‐MDB, was developed for phosphorescence and time‐gated luminescence quantification of H2S using a responsive luminescence‐masking moiety. Monitoring and visualization of H2S in cell lysosomes, D. magna, zebrafish, organs, mice, and human sera, is possible. Key: electron transfer (ET), emission (Em), excitation (Ex).
A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable ...unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications.
Ionic liquids (ILs) are a special category of molten salts solely composed of ions with varied molecular symmetry and charge delocalization. The versatility in combining varied cation–anion moieties ...and in functionalizing ions with different atoms and molecular groups contributes to their peculiar interactions ranging from weak isotropic associations to strong, specific, and anisotropic forces. A delicate interplay among intra- and intermolecular interactions facilitates the formation of heterogeneous microstructures and liquid morphologies, which further contributes to their striking dynamical properties. Microstructural and dynamical heterogeneities of ILs lead to their multifaceted properties described by an inherent designer feature, which makes ILs important candidates for novel solvents, electrolytes, and functional materials in academia and industrial applications. Due to a massive number of combinations of ion pairs with ion species having distinct molecular structures and IL mixtures containing varied molecular solvents, a comprehensive understanding of their hierarchical structural and dynamical quantities is of great significance for a rational selection of ILs with appropriate properties and thereafter advancing their macroscopic functionalities in applications. In this review, we comprehensively trace recent advances in understanding delicate interplay of strong and weak interactions that underpin their complex phase behaviors with a particular emphasis on understanding heterogeneous microstructures and dynamics of ILs in bulk liquids, in mixtures with cosolvents, and in interfacial regions.
In order to show how the teacher spreads the international Chinese language and Chinese culture for the foreign audience group through the classroom teaching behavior, and to shape the communication ...mechanism of the national image of China, with the help of the classical theory models of communication, this paper analyzed the role of international Chinese education in the transmission of China’s national image. The conclusion shows that international Chinese education is an effective way to build China’s image. It can not only show China’s image objectively and truly, but also offset the negative noise.
Display omitted
Rechargeable sodium-ion batteries (SIBs) have attracted great attention for large-scale electric energy storage applications and smart grid owing to the abundance of Na resources and ...comparable performance with lithium-ion batteries. The use of organic electrode materials enables a sodium storage system with high energy/power density, metal-free, environmental friendliness, flexibility, lightweight, and cost-effectiveness. More importantly, the structural diversity and the ease of functionalizing organic molecules allows straightforward controllability on the redox properties and thus on the battery performances. Despite the development of organic SIBs is still in its infant state, they have drawn dramatically growing attentions and shown great promises throughout research works. In this review, we summarize the research efforts to push forward the electrochemical performance of the organic SIBs. We explore the efforts made on molecular design and electrode design, and the combination of both forms the basis to regulate the electrochemical properties. Moreover, we summarize the strategies for reducing the solubility of the organic electrode materials in light of the importance of this issue. The crucial differences between organic lithium-ion batteries and organic SIBs are presented. Finally, future challenges and opportunities of further developing organic electrode materials are discussed.
Potassium-ion batteries are a promising alternative to lithium-ion batteries. However, it is challenging to achieve fast charging/discharging and long cycle life with the current electrode materials ...because of the sluggish potassiation kinetics. Here we report a soft carbon anode, namely highly nitrogen-doped carbon nanofibers, with superior rate capability and cyclability. The anode delivers reversible capacities of 248 mAh g
at 25 mA g
and 101 mAh g
at 20 A g
, and retains 146 mAh g
at 2 A g
after 4000 cycles. Surface-dominated K-storage is verified by quantitative kinetics analysis and theoretical investigation. A full cell coupling the anode and Prussian blue cathode delivers a reversible capacity of 195 mAh g
at 0.2 A g
. Considering the cost-effectiveness and material sustainability, our work may shed some light on searching for K-storage materials with high performance.
Solvent free ionic liquid (IL) electrolytes facilitate high‐voltage supercapacitors with enhanced energy density, but their complex ion arrangement and through that the electrochemical properties, ...are limited by strong Coulombic ordering in the bulk state and like‐charged ion repulsion at electrified interfaces. Herein, a unique interfacial phenomenon resulting from the presence of carbon dioxide loaded in 1‐Ethyl‐3‐methylimidazoliumtetrafluorborate electrolyte that simultaneously couples to IL ions and nitrogen‐doped carbonaceous electrode is reported. The adsorbed CO2 molecule polarizes and mitigates the electrostatic repulsion among like‐charged ions near the electrified interface, leading to an ion “bridge effect” with increased interfacial ionic density and significantly enhanced charge storage capability. The unpolarized CO2 possessing a large quadrupole moment further reduces ion coupling, resulting in higher conductivity of the bulk IL and improved rate capability of the supercapacitor. This work demonstrates polarization‐controlled like‐charge attraction at IL–electrode–gas three‐phase boundaries, providing insights into manipulating complex interfacial ion ordering with small polar molecule mediators.
Solvent‐free ionic liquid (IL) electrolytes enable high‐voltage and high‐energy‐density applications. The proposed bridge effect with CO2 loaded in an IL electrolyte acting as a mediator on the nitrogen‐doped electrode surface, alleviates the undesired Coulombic ordering and interfacial like‐charged ion repulsion. By breaking the limitation of interfacial ion packing density, this effect results in a significant enhancement of charge storage capability.
Rewritable artificial magnetic charge ice Wang, Yong-Lei; Xiao, Zhi-Li; Snezhko, Alexey ...
Science (American Association for the Advancement of Science),
05/2016, Letnik:
352, Številka:
6288
Journal Article
Recenzirano
Odprti dostop
Artificial ices enable the study of geometrical frustration by design and through direct observation. However, it has proven difficult to achieve tailored long-range ordering of their diverse ...configurations, limiting both fundamental and applied research directions. We designed an artificial spin structure that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. We also developed a technique to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multifunctionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice could provide a setting for designing magnetic monopole defects, tailoring magnonics, and controlling the properties of other two-dimensional materials.
The development of novel functional nanostructures and the implementation of an asymmetric cell design are the key challenges to increase the electrochemical performance of aqueous based ...supercapacitors. In this manuscript complex three-dimensional electrode materials are nano-engineered based on free-standing open-ended core/shell nanotube arrays with tailored functions. Both the negative and positive electrode materials are designed and nanostructured individually, using an innovative material combination of Polypyrrole (PPy) and manganese oxide (MnO2). This asymmetric cell design increases the possible operating potential window to 1.7V, which is a major leap to enhance the specific energy of supercapacitors. The prepared device exhibits a high specific energy of 27.2Whkg−1 and a high specific power 24.8kWkg−1.
Display omitted
•We realized a 3D nano-engineered aqueous based asymmetric supercapacitor.•The 3D asymmetric supercapacitor has advanced core/shell nanotubes on both electrodes.•The asymmetric cell design results in a high operating cell voltage of 1.7V.•The asymmetric device exhibits a specific energy of 27.2Whkg−1 at 0.85kWkg−1.
Reversible regulation of membrane microstructures via non‐covalent interactions is of considerable interest yet remains a challenge. Herein, we discover a general one‐step approach to fabricate ...supramolecular porous polyelectrolyte membranes (SPPMs) from a single poly(ionic liquid) (PIL). The experimental results and theoretical simulation suggested that SPPMs were formed by a hydrogen‐bond‐induced phase separation of a PIL between its polar and apolar domains, which were linked together by water molecules. This unique feature was capable of modulating microscopic porous architectures and thus the global mechanical property of SPPMs by a rational design of the molecular structure of PILs. Such SPPMs could switch porosity upon thermal stimuli, as exemplified by dynamically adaptive transparency to thermal fluctuation. This finding provides fascinating opportunities for creating multifunctional SPPMs.
Supramolecular porous polyelectrolyte membranes are constructed by utilizing water as cross‐linker from a single poly(ionic liquid). Owing to the intrinsic dynamic nature of hydrogen bonding, these SPPMs could switch porosity upon thermal stimuli, which is exemplified by dynamically adaptive transparency to thermal fluctuation.
PDF
