Lithium metal anodes offer high theoretical capacities (3,860 milliampere-hours per gram)
, but rechargeable batteries built with such anodes suffer from dendrite growth and low Coulombic efficiency ...(the ratio of charge output to charge input), preventing their commercial adoption
. The formation of inactive ('dead') lithium- which consists of both (electro)chemically formed Li
compounds in the solid electrolyte interphase and electrically isolated unreacted metallic Li
(refs
)-causes capacity loss and safety hazards. Quantitatively distinguishing between Li
in components of the solid electrolyte interphase and unreacted metallic Li
has not been possible, owing to the lack of effective diagnostic tools. Optical microscopy
, in situ environmental transmission electron microscopy
, X-ray microtomography
and magnetic resonance imaging
provide a morphological perspective with little chemical information. Nuclear magnetic resonance
, X-ray photoelectron spectroscopy
and cryogenic transmission electron microscopy
can distinguish between Li
in the solid electrolyte interphase and metallic Li
, but their detection ranges are limited to surfaces or local regions. Here we establish the analytical method of titration gas chromatography to quantify the contribution of unreacted metallic Li
to the total amount of inactive lithium. We identify the unreacted metallic Li
, not the (electro)chemically formed Li
in the solid electrolyte interphase, as the dominant source of inactive lithium and capacity loss. By coupling the unreacted metallic Li
content to observations of its local microstructure and nanostructure by cryogenic electron microscopy (both scanning and transmission), we also establish the formation mechanism of inactive lithium in different types of electrolytes and determine the underlying cause of low Coulombic efficiency in plating and stripping (the charge and discharge processes, respectively, in a full cell) of lithium metal anodes. We propose strategies for making lithium plating and stripping more efficient so that lithium metal anodes can be used for next-generation high-energy batteries.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Owing to the increasing need to mitigate excessive organic solvent waste, the efficient separation and recovery of organic solvents have received major research attention in recent years. The ...membrane‐based organic solvent nanofiltration (OSN) process has demonstrated its feasibility in addressing this problem with low energy costs, compared to conventional separation techniques, such as adsorption, liquid–liquid extraction, and solvent evaporation. Recently, membranes made of 2D graphene‐based materials have shown great promise because they attain high solvent flux and solute rejection using easy processing methods. Thus, this paper focuses on state‐of‐the‐art studies of graphene‐based membranes used in OSN processes, which include syntheses, characterizations, performance evaluations, membrane fouling, and simulation studies, in combination with the development of the “upper‐bound” line to indicate the performance of graphene‐based membranes. In this paper, critical challenges involved in the development of graphene‐based membranes are also focused on and discussed to map out the future directions of these membranes in industrial OSN processes. In addition to OSN, this paper pertains to a broader audience in other separation processes, particularly in the fields of gas separation and water treatment.
Graphene‐based membranes have attracted substantial attention among researchers in the field of molecular separation. Due to the great stability of graphene and its derivatives, the potential of graphene‐based membranes in organic solvent nanofiltration has been promising, as high solute (organic dyes, active pharmaceutical ingredients and drugs) rejection is achievable, creating high‐purity organic solvent in the permeate stream.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Single-cell transcriptome profiling of tumour tissue isolates allows the characterization of heterogeneous tumour cells along with neighbouring stromal and immune cells. Here we adopt this powerful ...approach to breast cancer and analyse 515 cells from 11 patients. Inferred copy number variations from the single-cell RNA-seq data separate carcinoma cells from non-cancer cells. At a single-cell resolution, carcinoma cells display common signatures within the tumour as well as intratumoral heterogeneity regarding breast cancer subtype and crucial cancer-related pathways. Most of the non-cancer cells are immune cells, with three distinct clusters of T lymphocytes, B lymphocytes and macrophages. T lymphocytes and macrophages both display immunosuppressive characteristics: T cells with a regulatory or an exhausted phenotype and macrophages with an M2 phenotype. These results illustrate that the breast cancer transcriptome has a wide range of intratumoral heterogeneity, which is shaped by the tumour cells and immune cells in the surrounding microenvironment.
The electrocatalytic conversion of CO2 to value‐added hydrocarbons is receiving significant attention as a promising way to close the broken carbon‐cycle. While most metal catalysts produce C1 ...species, such as carbon monoxide and formate, the production of various hydrocarbons and alcohols comprising more than two carbons has been achieved using copper (Cu)‐based catalysts only. Methods for producing specific C2 reduction outcomes with high selectivity, however, are not available thus far. Herein, the morphological effect of a Cu mesopore electrode on the selective production of C2 products, ethylene or ethane, is presented. Cu mesopore electrodes with precisely controlled pore widths and depths were prepared by using a thermal deposition process on anodized aluminum oxide. With this simple synthesis method, we demonstrated that C2 chemical selectivity can be tuned by systematically altering the morphology. Supported by computational simulations, we proved that nanomorphology can change the local pH and, additionally, retention time of key intermediates by confining the chemicals inside the pores.
I pity the pore intermediate: Nanomorphology‐directed C2‐product selectivity was demonstrated on a Cu mesopore electrode. A local flow field is generated on the electrode surface and confines reaction intermediates inside the pore. The prolonged retention time of the intermediates affects the kinetics of protonation and C−C bond formation, determining the final C2 product.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Air-transmitted pathogens may cause severe epidemics showing huge threats to public health. Microbial inactivation in the air is essential, whereas the feasibility of existing air disinfection ...technologies meets challenges including only achieving physical separation but no inactivation, obvious pressure drops, and energy intensiveness. Here we report a rapid disinfection method toward air-transmitted bacteria and viruses using the nanowire-enhanced localized electric field to damage the outer structures of microbes. This air disinfection system is driven by a triboelectric nanogenerator that converts mechanical vibration to electricity effectively and achieves self-powered. Assisted by a rational design for the accelerated charging and trapping of microbes, this air disinfection system promotes microbial transport and achieves high performance: >99.99% microbial inactivation within 0.025 s in a fast airflow (2 m/s) while only causing low pressure drops (<24 Pa). This rapid, self-powered air disinfection method may fill the urgent need for air-transmitted microbial inactivation to protect public health.
Expedition of electron transfer efficiency and optimization of surface reactant adsorption products desorption processes are two main challenges for developing non‐noble catalysts in the oxygen ...reduction reaction (ORR) and CO2 reduction reaction (CRR). A heterojunction prototype on Co3S4@Co3O4 core–shell octahedron structure is established via hydrothermal lattice anion exchange protocol to implement the electroreduction of oxygen and carbon dioxide with high performance. The synergistic bifunctional catalyst consists of p‐type Co3O4 core and n‐type Co3S4 shell, which afford high surface electron density along with high capacitance without sacrificing mechanical robustness. A four electron ORR process, identical to the Pt catalyzed ORR, is validated using the core–shell octahedron catalyst. The synergistic interaction between cobalt sulfide and cobalt oxide bicatalyst reduces the activation energy to convert CO2 into adsorbed intermediates and hereby enables CRR to run at a low overpotential, with formate as the highly selective main product at a high faraday efficiency of 85.3%. The remarkable performance can be ascribed to the synergistic coupling effect of the structured co‐catalysts; heterojunction structure expedites the electron transfer efficiency and optimizes surface reactant adsorption product desorption processes, which also provide theoretical and pragmatic guideline for catalyst development and mechanism explorations.
A heterojunction formed by the Co3S4@Co3O4 core–shell octahedrons largely contributes to the high performance in supercapacitors, oxygen reduction reactions, and carbon dioxide reduction reactions because of the improved surface electron density, electron transfer efficiency, surface reactant adsorption products desorption process, and synergistic effect between Co3S4 and Co3O4. Such a heterojunction also prevents active sites leaching and leads to high catalytic stability.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Targeted protein degradation allows targeting undruggable proteins for therapeutic applications as well as eliminating proteins of interest for research purposes. While several degraders that harness ...the proteasome or the lysosome have been developed, a technology that simultaneously degrades targets and accelerates cellular autophagic flux is still missing. In this study, we develop a general chemical tool and platform technology termed AUTOphagy-TArgeting Chimera (AUTOTAC), which employs bifunctional molecules composed of target-binding ligands linked to autophagy-targeting ligands. AUTOTACs bind the ZZ domain of the otherwise dormant autophagy receptor p62/Sequestosome-1/SQSTM1, which is activated into oligomeric bodies in complex with targets for their sequestration and degradation. We use AUTOTACs to degrade various oncoproteins and degradation-resistant aggregates in neurodegeneration at nanomolar DC
values in vitro and in vivo. AUTOTAC provides a platform for selective proteolysis in basic research and drug development.
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•The levels of PFAS in the multimedia environment of Asan Lake area were examined.•PFOA in air and soil, PFPeA in water, and PFOS in sediment and fish were majors.•Long-chain PFAS ...were dominant PFAS in most media except water.•Longer-chain PFAS, especially PFOS, are significantly accumulated in fish.•PCA result implies that PFAS in fish might be transferred from the sediment.
Seasonal and spatial variations in per- and polyfluoroalkyl substances (PFAS) concentrations in different environmental media in the Asan Lake area of South Korea were investigated by measuring liquid chromatography-tandem mass spectrometry (LC–MS/MS). The mean concentrations of Σ16 PFAS in the different media were in the ranges of 20.7–98.2 pg/m3 in air, 17.7–467 ng/L in water, 0.04–15.0 ng/g dry weight (dw) in sediments, and not detected (n.d.)–12.9 ng/g dw in soils, and the mean concentrations of Σ19 PFAS in fish ranged from n.d. to 197 ng/g wet weight. The most frequently detected PFAS were perfluorooctanoic acid (PFOA) in air and soils, perfluoropentanoic acid (PFPeA) in water, and perfluorooctane sulfonate (PFOS) in sediment and fish. Long-chain PFAS species dominated over short-chain PFAS in most media samples except for the water phase. Sediment-water partition coefficients (log Kd) and bioaccumulation factors (log BAF) of PFAS were calculated using measured concentrations in water, sediments, and fish. Log Kd of PFAS tended to increase with increasing CF2 units of PFAS, and perfluorodecanoic acid (PFDA) and PFOS showed the highest log BAF value (> 3.0) in all fish species. These results indicate that longer-chain PFAS, especially PFOS, can be effectively accumulated in biota such as fish.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A LiLi0.19Ni0.16Co0.08Mn0.57O2 cathode was coated with AlF3 on the surface. The AlF3‐coating enhanced the overall electrochemical characteristics of the electrode while overcoming the typical ...shortcomings of lithium‐enriched cathodes. This improvement was attributed to the transformation of the initial electrode layer to a spinel phase, induced by the Li chemical leaching effect of the AlF3 coating layer.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK