Despite the recent considerable progress, the reversibility and cycle life of silicon anodes in lithium-ion batteries are yet to be improved further to meet the commercial standards. The current major industry, instead, adopts silicon monoxide (SiOx, x ≈ 1), as this phase can accommodate the volume change of embedded Si nanodomains via the silicon oxide matrix. However, the poor Coulombic efficiencies (CEs) in the early period of cycling limit the content of SiOx, usually below 10 wt % in a composite electrode with graphite. Here, we introduce a scalable but delicate prelithiation scheme based on electrical shorting with lithium metal foil. The accurate shorting time and voltage monitoring allow a fine-tuning on the degree of prelithiation without lithium plating, to a level that the CEs in the first three cycles reach 94.9%, 95.7%, and 97.2%. The excellent reversibility enables robust full-cell operations in pairing with an emerging nickel-rich layered cathode, Li[Ni0.8Co0.15Al0.05]O2, even at a commercial level of initial areal capacity of 2.4 mAh cm(-2), leading to a full cell energy density 1.5-times as high as that of graphite-LiCoO2 counterpart in terms of the active material weight.

Efficient CO 2 scrubbing without a significant energy penalty remains an outstanding challenge for the fossil fuel-burning industry where aqueous amine solutions are still widely used. Porous materials have long been evaluated for next generation CO 2 adsorbents. Porous polymers, robust and inexpensive, show promise as feasible materials for the capture of CO 2 from warm exhaust fumes. We report the syntheses of porous covalent organic polymers (COPs) with CO 2 adsorption capacities of up to 5616 mg g À1 (measured at high pressures, i.e. 200 bar) and industrially relevant temperatures (as warm as 65 C). COPs are stable in boiling water for at least one week and near infinite CO 2 /H 2 selectivity is observed.

We report supramolecular cross-linking of polymer binders via dynamic host-guest interactions between hyperbranched β-cyclodextrin polymer and a dendritic gallic acid cross-linker incorporating six adamantane units for high-capacity silicon anodes. Calorimetric analysis in the solution phase indicates that the given host-guest complexation is a highly spontaneous and enthalpically driven process. These findings are further verified by carrying out gelation experiments in both aqueous and organic media. The dynamic cross-linking process enables intimate silicon-binder interaction, structural stability of electrode film, and controlled electrode-electrolyte interface, yielding enhanced cycling performance. Control experiments using both α, γ-CDp with different cavity sizes and a guest molecule incorporating a single adamantane unit verified that the enhanced cycle life originates from the host-guest interaction between β-cyclodextrin and adamantane. The impact of the dynamic cross-linking is maximized at an optimal stoichiometry between the two components. Importantly, the present investigation proves that the molecular-level tuning of the host-guest interactions can be translated directly to the cycling performance of silicon anodes.

Carbon dioxide capture and separation requires robust solids that can stand harsh environments where a hot mixture of gases is often found. Herein, the fi rst and comprehensive syntheses of porous sulfur-bridged covalent organic polymers (COPs) and their application for carbon dioxide capture in warm conditions and a wide range of pressures (0-200 bar) are reported. These COPs can store up to 3294 mg g − 1 of carbon dioxide at 318 K and 200 bar while being highly stable against heating up to 400 ° C. The carbon dioxide capacity of the COPs is also not hindered upon boiling in water for at least one week. Physisorptive binding is prevalent with isosteric heat of adsorptions around 24 kJ mol − 1 . M06-2X and RIMP2 calculations yield the same relative trend of binding energies, where, interestingly, the dimer of triazine and benzene play a cooperative role for a stronger binding of CO 2 (19.2 kJ mol − 1 ) as compared to a separate binding with triazine (13.3 kJ mol − 1 ) or benzene (11.8 kJ mol − 1 ).

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Allosteric information transfer in proteins has been linked to distinct vibrational energy transfer (VET) pathways in an umber of theoretical studies.E xperimental evidence for such pathways, however,i ss parse because site-selective injection of vibrational energy into aprotein, that is,localized heating,isrequired for their investigation. Here,wesolved this problem by the site-specific incorporation of the non-canonical amino acid b-(1-azulenyl)-l-alanine (AzAla) through genetic code expansion. As an exception to Kashasr ule,A zAla undergoes ultrafast internal conversion and heating after S 1 excitation while upon S 2 excitation, it serves as af luorescent label. We equipped PDZ3, ap rotein interaction domain of postsynaptic density protein 95, with this ultrafast heater at two distinct positions.W eindeed observed VET from the incorporation sites in the protein to ab ound peptide ligand on the picosecond timescale by ultrafast IR spectroscopy. This approach based on genetically encoded AzAla paves the way for detailed studies of VET and its role in aw ide range of proteins. Dr.J .Jaric Present address:H ospira Zagreb d.o.o.,aPfizer company Prudnicka cesta 60, 10291 Prigorje Brdovecko (Croatia) [ + + ]T hese authors contributed equally to this work. Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

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Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiO composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO]. During the dynamic course of spray pyrolysis, [SiO] transforms to SiO matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiO composite, in which Si nanodomains are homogeneously embedded in the SiO matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate.