Ultrathin and Air-Stable Lithium Metal Anodes with Superlong Cycling Life in Ether/Ester-Based Electrolytes

Ultrathin and air-stable Li metal anodes hold great promise toward high-energy and high-safety Li metal batteries(LMBs).However,the application of LMBs is technically impeded by existing Li metal anodes with large thickness,high reactivity,and poor performance.Here,we developed a novel and scalable approach for the construction of a 10-μm-thick flexible and air-stable Li metal anode by conformally encapsulating Li within a multifunctional VN film.Specifically,the highly lithiophilic VN layer guides a uniform deposition of Li,while abundant and multilevel pores arising from assembly of ultrathin nanosheets enable a spatially confined immersion of metallic Li,thus ensuring an ultrathin and sandwiched Li anode.More impressively,the strong hydrophobicity of VN surface can effectively improve the stability of anode to humid air,whereas the highly conductive framework greatly boosts charge transfer dynamics and enhances Li utilization and high-rate capability.Benefiting from such fascinating features,the constructed Li-VN anode exhibits ultrastable cycling stability in both ether(2500 h)and carbonate(900 h)electrolytes,respectively.Moreover,even exposed to ambient air for 12 h,the anode still can retain~78%capacity,demonstrating excellent air-defendable capability.This work affords a promising strategy for fabricating high-performance,high-safety,and low-cost LMBs.

Air Stable Chalcogen-Doped Rubicenes with Diradical Character

Air stable diradicaloid polycyclic aromatic hydrocarbon(PAH)materials possess unique electronic and magnetic properties for various applications.In general,long conjugated distances between two radical centers are required to improve the air stability,thereby complicating the synthetic procedures.Herein,the chalcogen containing rubicenes(O-,S-,and Se-rubicenes)were systematically investigated to understand the chalcogen effects on chalcogen-rubicene physicochemical properties.Impressively,these rubicenes presented unprecedented diradical characterwithin one simple benzene ring and excellent air stabilities.Theirdiradicalcharacterweremanifested by single-crystal X-ray studies,variable-temperature nuclear magnetic resonance,and electron spin resonance.Furthermore,the nucleus independent chemical shifts andthe anisotropy of the induced currentdensity calculations revealed that the formation of diradical was caused by a pro-aromaticity driving force.Importantly,the diradical character of rubicenes are visualizedbyFractionalOccupationNumberWeighted Electron Density(FOD)plots,which present high NFOD values from 1.651 to 1.830.This contribution provided distinctive insights into the structure and property relationship of PAH diradicals.

Circulating Neutrophil Counts Decrease in Response to Mitigated Air Quality in Stable COPD Patients

This three-year study, based on the Guangzhou Institute of Respiratory Disease （GRID）, chronic obstructive pulmonary disease （COPD） Biobank, was conducted in 36 COPD patients to estimate whether changes in levels of leukocytes, erythrocytes, hemoglobin, and platelets were related to changes in air pollutant concentration. Daily NO2 levels exhibited significant differences between baseline years and the 2010 Asian Game period. We observed significant reductions in leukocyte and neutrophils counts levels, by 15.51% and 23.01%, from pre-Asian Games to during-Asian Games, respectively. In the post-Asian Game period, most pollutants approximated pre-Asian Game period levels, and similar effects were demonstrated in leukocyte and neutrophil counts. For both items, we identified significant increases resulting from elevated NO2 at lag days 0-2/5-6. We concluded that reductions in pollutants during the intervention period were associated with inactivation of hematological events in COPD.

Air-stable inorganic solid-state electrolytes for high energy density lithium batteries: Challenges, strategies, and prospects

Solid-state batteries have been considered as promising next-generation energy storage devices for potentially higher energy density and better safety compared with commercial lithium-ion batteries that are based on organic liquid electrolytes.However,in terms of indispensable solid-state electrolytes,there are remaining issues to be solved before entering the market.Most solid-state electrolytes are air-sensitive,which causes a complex and expensive cell assembly and impressible interface.Therefore,the solid-state electrolytes are expected to be atmosphere-stable,which will undoubtedly bring significant benefits to solid-state battery manufacturing.This review covers air-stabilityrelated issues of different types of inorganic solid-state electrolytes and the corresponding strategies.First,we provide an overview of solid-state electrolytes and solid-state batteries,including their history and advantages/disadvantages.Then,different types of solid-state electrolytes are selected as examples to illustrate the unfavorable interactions in air and the corresponding adverse effects.Next,according to recent advances,we summarize the effective strategies of constructing different types of air-stable inorganic solid-state electrolytes.Finally,perspectives on designing accessible air-stable solid-state electrolytes are provided,aiming to achieve the assembly of high-performance solid-state batteries in the atmosphere.

Getting rid of NaBH4:Gold seeds reduced by air-stable agents for synthesizing quasi one-dimensional gold nanoparticles

Herein,we have presented a novel and easy to operate seed-mediated system for fabricating gold bipyramids(AuBPs)with 85%yields without any separation/purification processes.The used gold seeds are reduced by tannin and citrate,two kinds of air stable ligands,and conventio nally employed unstable NaBH4 are thoroughly cast off.In addition,the as-proposed gold seeds can also be employed for AuNRs fabrication with rather larger diameters(22.2-60.3 nm),which is difficult to be achieved by conve ntional seed mediated fabrication system.

Simulation analysis for controlling temperature stability of a radiant-board system served for thermodynamic temperature measurement laboratory

Fundamental metrology is closely tied to scientific advancement and requires well-equipped facilities to achieve low measurement uncertainty in rigorous experiments.Addressing the±0.1 K high-stability temperature control issue of the precision laboratory radiant air conditioning system,this study investigated the influence of different radiant panel area ratios,laying methods,cold source water supply temperature fluctuations,and external environmental disturbances by simulations.The results indicate that:(1)the larger the ratio of radiant panel area,the greater the fluctuation in equipment surface temperature;(2)the surface temperature of the measurement equipment can satisfy±0.1 K control temperature stability requirement when the fluctuations of the surface temperature of radiant panels and glass window are within±0.5 K and±1 K respectively without radiant panels on the ceiling;(3)the surface temperature of the measurement equipment can satisfy±0.1 K control temperature stability requirement when the fluctuations of the surface temperature of radiant panels and glass window are within±0.2 K and±2 K respectively with radiant panels on the ceiling.This study provides a reference for the design and operation control of air conditioning systems in fundamental metrology.

Robust n-type doping of WSe2 enabled by controllable proton irradiation

Two-dimensional(2D)transition metal dichalcogenides(TMDs)are considered to be promising building blocks for the next generation electronic and optoelectronic devices.Various doping schemes and work function engineering techniques have been explored to overcome the intrinsic performance limits of 2D TMDs.However,a reliable and long-time air stable doping scheme is still lacking in this field.In this work,we utilize keV ion beams of H2+to irradiate layered WSe2 crystals and obtain efficient n-type doping effect for all irradiated crystals within a fluence of 1×1014 protons·cm−2(1e14).Moreover,the irradiated WSe2 remains an n-type semiconductor even after it is exposed to ambient conditions for a year.Localized ion irradiation with a focused beam can directly pattern on the sample to make high performance homogenous p-n junction diodes.Raman and photoluminescence(PL)spectra demonstrate that the WSe2 crystal lattice stays intact after irradiation within 1e14.We attribute the reliable electrondoping to the significant increase in Se vacancies after the proton irradiation,which is confirmed by our scanning transmission electron microscope(STEM)results.Our work demonstrates a reliable and long-term air stable n-type doping scheme to realize high-performance electronic TMD devices,which is also suitable for further integration with other 2D devices.

Enormous enhancement in electrical performance of few-layered MoTe2 due to Schottky barrier reduction induced by ultraviolet ozone treatment

Doping can improve the band alignment at the metal-semiconductor interface to modify the corresponding Schottky barrier,which is crucial for the realization of high-performance logic components.Here,we systematically investigated a convenient and effective method,ultraviolet ozone treatment,for p-type doping of MoTe2 field-effect transistors to enormously enhance the corresponding electrical performance.The resulted hole concentration and mobility are near 100 times enhanced to be〜1.0×10^13 cm^-2 and 101.4 cm^2/(V·s),respectively,and the conductivity is improved by 5 orders of magnitude.These values are comparable to the highest ones ever obtained via annealing doping or non-lithographic fabrication methods at room temperature.Compared with the pristine one,the photoresponsivity(522 mA/W)is enhanced approximately 100 times.Such excellent performances can be attributed to the sharply reduced Schottky barrier because of the surface charge transfer from MoTe2 to MoOx(x<3),as proved by photoemission spectroscopy.Additionally,the p-doped devices exhibit excellent stability in ambient air.Our findings show significant potential in future nanoelectronic and optoelectronic applications.