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Li+-conductive ceramic oxide electrolytes, such as garnet-structured Li7La3Zr2O12, have been considered as promising candidates for realizing the next-generation solid-state Li-metal batteries with high energy density. Practically, the ceramic pellets sintered at elevated temperatures are often provided with high stiffness yet low fracture toughness, making them too brittle for the manufacture of thin-film electrolytes and strain-involved operation of solid-state batteries. The ceramic powder, though provided with ductility, does not yield satisfactorily high Li+ conductivity due to poor ion conduction at the boundaries of ceramic particles. Here we show, with solid-state nuclear magnetic resonance, that a uniform conjugated polymer nanocoating formed on the surface of ceramic oxide particles builds pathways for Li+ conduction between adjacent particles in the unsintered ceramics. A tape-casted thin-film electrolyte (thickness

Sulfide-based solid-state electrolytes (SSEs) matched with alloy anodes are considered as promising candidates for application in all-solid-state batteries (ASSBs) to overcome the bottlenecks of the lithium (Li) anode. However, an understanding of the dynamic electrochemical processes on alloy anode in SSE is still elusive. Herein, in situ atomic force microscopy gives insights into the block-formation and stack-accumulation behaviors of Li precipitation on an Li electrode, uncovering the morphological evolution of nanoscale Li deposition/dissolution in ASSBs. Furthermore, two-dimensional Li-indium (In) alloy lamellae and the homogeneous solid electrolyte interphase (SEI) shell on the In electrode reveal the precipitation mechanism microscopically regulated by the alloy anode. The flexible and wrinkle-structure SEI shell further enables the electrode protection and inner Li accommodation upon cycles, elucidating the functional influences of SEI shell on the cycling behaviors. Such on-site tracking of the morphological evolution and dynamic mechanism provide an in-depth understanding and thus benefit the optimizations of alloy-based ASSBs.

Solid-state Li-metal batteries offer a great opportunity for high-security and high-energy-density energy storage systems. However, redundant interfacial modification layers, intended to lead to an overall satisfactory interfacial stability, dramatically debase the actual energy density. Herein, a dual-interface amorphous cathode electrolyte interphase/solid electrolyte interphase CEI/SEI protection (DACP) strategy is proposed to conquer the main challenges of electrochemical side reactions and Li dendrites in hybrid solid-liquid batteries without sacrificing energy density via LiDFOB and LiBF4 in situ synergistic conversion. The amorphous CEI/SEI products have an ultralow mass proportion and act as a dynamic shield to cooperatively enforce dual electrodes with a well-preserved structure. Thus, this in situ DACP layer subtly reconciles multiple interfacial compatibilities and a high energy density, endowing the hybrid solid-liquid Li-metal battery with a sustainably brilliant cycling stability even at practical conditions, including high cathode loading, high voltage (4.5 V), and high temperature (45 °C) conditions, and enables a high-energy-density (456 Wh kg-1) pouch cell (11.2 Ah, 5 mA h cm-2) with a lean electrolyte (0.92 g Ah-1, containing solid and liquid phases). The compatible modification strategy points out a promising approach for the design of practical interfaces in future solid-state battery systems.

Li

The fast-ionic-conducting ceramic electrolyte is promising for next-generation high-energy-density Li-metal batteries, yet its application suffers from the high interfacial resistance and poor interfacial stability. In this study, the compatible solid-state electrolyte was designed by coating Li1.4Al0.4Ti1.6(PO4)3 (LATP) with polyacrylonitrile (PAN) and polyethylene oxide (PEO) oppositely to satisfy deliberately the disparate interface demands. Wherein, the upper PAN constructs soft-contact with LiNi0.6Mn0.2Co0.2O2, and the lower PEO protects LATP from being reduced, guaranteeing high-voltage tolerance and improved stability toward Li-metal anode performed in one ceramic. Moreover, the core function of LATP is amplified to guide homogeneous ions distribution and hence suppresses the formation of a space-charge layer across interfaces, uncovered by the COMSOL Multiphysics concentration field simulation. Thus, such a bifunctional modified ceramic electrolyte integrates the respective superiority to render Li-metal batteries with excellent cycling stability (89% after 120 cycles), high Coulombic efficiency (exceeding 99.5% per cycle), and a dendrite-free Li anode at 60 °C, which represents an overall design of ceramic interface engineering for future practical solid battery systems.

The conductive framework is generating considerable interest for lithium metal anodes to accommodate Li+ deposition, due to its ability to reduce electrode current density by increasing the deposition area. However, in most cases, the electroactive surface area is not fully utilized for the nucleation of Li in 3D current collectors, especially under high current densities. Herein, uniform nucleation of Li in the conductive skeleton is achieved by a two-step synergetic process arising from CuBr- and Br-doped graphene-like film. The modified electrode regulates Li nucleating in uniform pancake-like seeds and growing into a granular Li metal ascribed to the excellent lithiophilicity of CuBr- and Br-doping sites and the low Li diffusion barrier on the surface of generated LiBr, as confirmed by the experimental and computational results. Therefore, the modified anode endows small nucleation overpotential, a high-reversibility Li plating/stripping process, and excellent performance in full batteries with indust...

The key bottleneck troubling the application of solid electrolyte is the contradictory requirements from Li-metal and cathode, which need high modulus to block Li-dendrite penetration and flexibility to enable low interface resistance, respectively. This study describes a thin asymmetrical design of solid electrolyte to address these shortcomings. In this architecture, a rigid ceramic-layer modified with an ultrathin polymer is toward Li-metal to accomplish dendrite-suppression of Li-anode, and a soft polymer-layer spreads over the exterior and interior of cathode to endow connected interface simultaneously. This ingenious arrangement endows solid Li-metal batteries with extremely high Coulombic efficiency and cyclability. This work will open up one avenue for realizing safe and long-life energy storage systems.

A concise deracemization of racemic secondary and tertiary amines with a tetrahydroisoquinoline core has been successfully realized by orchestrating a redox process consisted of N-bromosuccinimide oxidation and iridum-catalyzed asymmetric hydrogenation. This compatible redox combination enables one-pot, single-operation deracemization to generate chiral 1-substituted 1,2,3,4-tetrahydroisoquinolines with up to 98% ee in 93% yield, offering a simple and scalable synthetic technique for chiral amines directly from racemic starting materials.

An efficient palladium-catalyzed asymmetric hydrogenation via capture of an active intermediate generated in situ from acid-catalyzed aza-Pinacol rearrangement has been successfully developed, providing efficient access to chiral exocyclic amines with up to 98% ee. Three-, four-, and five-membered cyclic N-sulfonyl amino alcohols are viable substrates. This study opens a new window to the application of asymmetric hydrogenation.

Structural and functional properties of integral membrane proteins are often studied in detergent micellar environments (proteomicelles), but how such proteomicelles form and organize is not well understood. This makes it difficult to evaluate the relationship between the properties of the proteins measured in such a detergent-solubilized form and under native conditions. To obtain mechanistic information about this relationship for the leucine transporter (LeuT), a prokaryotic homologue of the mammalian neurotransmitter/sodium symporters (NSSs), we studied the properties of proteomicelles formed by n-dodecyl-β,D-maltopyranoside (DDM) detergent. Extensive atomistic molecular dynamics simulations of different protein/detergent/water number ratios revealed the formation of a proteomicelle characterized by a constant-sized shell of detergents surrounding LeuT protecting its transmembrane segments from unfavorable hydrophobic/hydrophilic exposure. Regardless of the DDM content in the simulated system, this shell consisted of a constant number of DDM molecules (∼120 measured at a 4 Å cutoff distance from LeuT). In contrast, the overall number of DDMs in the proteomicelle (aggregation number) was found to depend on the detergent concentration, reaching a saturation value of 226±17 DDMs in the highest concentration regime simulated. Remarkably, we found that at high detergent-to-protein ratios we observed two independent ways of DDM penetration into LeuT, both leading to a positioning of the DDM molecule in the second substrate (S2) binding site of LeuT. Consonant with several recent experimental studies demonstrating changes in functional properties of membrane proteins due to detergent, our findings highlight how the environment in which the membrane proteins are examined may affect the outcome and interpretation of their mechanistic features.

Three novel bimetallic Au-Cu nanoclusters stabilized by a mixed layer of thiolate and phosphine ligands bearing pyridyl groups are synthesized and fully characterized by X-ray single crystal analysis and density functional theory computations. The three clusters have an icosahedral Au13 core face-capped by two, four, and eight Cu atoms, respectively. All face-capping Cu atoms in the clusters are triply coordinated by thiolate or pyridyl groups. The surface ligands control the exposure of Au sites in the clusters. In the case of the Au13Cu8 cluster, the presence of 12 2-pyridylthiolate ligands still leaves open space for catalysis. All the 3 clusters are 8-electron superatoms displaying optical gaps of 1.8-1.9 eV. The thermal decomposition studies suggest that the selective release of organic ligands from the clusters is possible.

This article presents a facile approach to centimeter-scale colloidal photonic crystals (PCs) with narrow stopbands assembled on low-adhesive superhydrophobic substrates. The full-width-at-half-maxima of the stopbands are just 12 nm. The narrow stopbands of colloidal PCs are ascribed to the combined effects of perfectly ordered assembly structure, large-scale crack elimination, decreased void fraction, and sufficient thickness of the colloidal PCs. These properties result from a self-assembly process on a low-adhesive superhydrophobic substrate. Latex suspension on this substrate displays a receding three-phase contact line during evaporation, which releases tensile stress induced by latex shrinkage and results in complete elimination of cracks in the colloidal PCs. Furthermore, the simultaneous assembly of latex particles on the outermost layer of a spread liquid film contributes to the perfectly ordered assembly structure. This facile fabrication of centimeter-scale colloidal PCs with narrow stopbands will offer significant insights into the design and creation of novel optical devices.

A new and easily regenerable NAD(P)H model 9,10-dihydrophenanthridine (DHPD) has been designed for biomimetic asymmetric hydrogenation of imines and aromatic compounds. This reaction features the use of hydrogen gas as terminal reductant for the regeneration of the DHPD under the mild condition. Therefore, the substrate scope is not limited in benzoxazinones; the biomimetic asymmetric hydrogenation of benzoxazines, quinoxalines, and quinolines also gives excellent activities and enantioselectivities. Meanwhile, an unexpected reversal of enantioselectivity was observed between the reactions promoted by the different NAD(P)H models, which is ascribed to the different hydride transfer pathway.

A catalytic amount of Hantzsch ester that could be regenerated in situ by Ru complexes under hydrogen gas has been employed in the biomimetic asymmetric hydrogenation of benzoxazinones with up to 99% ee in the presence of chiral phosphoric acid. The use of hydrogen gas as a reductant for the regeneration of Hantzsch esters makes this hydrogenation an ideal atom economic process.

In the development of vaccines for epithelial tumors, the key targets are MUC1 proteins, which have a variable number of tandem repeats (VNTR) bearing tumor-associated carbohydrate antigens (TACAs), such as Tn and STn. A major obstacle in vaccine development is the low immunogenicity of the short MUC1 peptide. To overcome this obstacle, we designed, synthesized, and evaluated several totally synthetic self-adjuvanting vaccine candidates with self-assembly domains. These vaccine candidates aggregated into fibrils and displayed multivalent B-cell epitopes under mild conditions. Glycosylation of Tn antigen on the Thr residue of PDTRP sequence in MUC1 VNTR led to effective immune response. These vaccines elicited a high level antibody response without any adjuvant and induced antibodies that recognized human breast tumor cells. These vaccines appeared to act through a T-cell independent pathway and were associated with the activation of cytotoxic T cells. These fully synthetic, molecularly defined vaccine candidates had several features that hold promise for anticancer therapy.

Residual dipolar couplings (RDCs) are widely used as orientation-dependent NMR restraints to improve the resolution of the NMR conformational ensemble of biomacromolecules and define the relative orientation of multidomain proteins and protein complexes. However, the interpretation of RDCs is complicated by the intrinsic degeneracy of analytical solutions and protein dynamics that lead to ill-defined orientations of the structural domains (ghost orientations). Here, we illustrate how restraints from paramagnetic relaxation enhancement (PRE) experiments lift the orientational ambiguity of multidomain membrane proteins solubilized in detergent micelles. We tested this approach on monomeric phospholamban (PLN), a 52-residue membrane protein, which is composed of two helical domains connected by a flexible loop. We show that the combination of classical solution NMR restraints (NOEs and dihedral angles) with RDC and PRE constraints resolves topological ambiguities, improving the convergence of the PLN structural ensemble and giving the depth of insertion of the protein within the micelle. The combination of RDCs with PREs will be necessary for improving the accuracy and precision of membrane protein conformational ensembles, where three-dimensional structures are dictated by interactions with the membrane-mimicking environment rather than compact tertiary folds common in globular proteins.

Five cationic surfactants, each bearing a single sulfur at various locations along their chains, were adsorbed into sodium dodecyl sulfate micelles. An oxidant, periodate, was added to the system, and the subsequent rate of thioether oxidation to sulfoxide, determined by NMR, was found to be diminished (more or less equally for all sulfur loci) by 2 orders of magnitude. In contrast, rates of hydrogen peroxide oxidation were hardly perturbed by micellization. Once again, however, there was no rate dependence on sulfur location within the chains. These results are interpreted in terms of a disordered micelle in which all chain positions have roughly equivalent access to the micelle surface. The kinetic method for assessing exposure to the external medium is applicable to self-assemblies and polymer systems wherever the NMR resolution so permits.

Asymmetric, regio- and stereoselective alternating copolymerization of CO(2) and racemic aliphatic epoxides proceeds effectively under mild temperature and pressure by using a binary catalyst system of a chiral tetradentate Schiff base cobalt complex [SalenCo(III)X] as the electrophile in conjunction with an ionic organic ammonium salt or a sterically hindered strong organic base as the nucleophile. The substituent groups on the aromatic rings, chiral diamine backbone, and axial X group of the electrophile, as well as the nucleophilicity, leaving ability, and coordination ability of the nucleophile, all significantly affect the catalyst activity, polymer selectivity, enantioselectivity, and stereochemistry. A bulky chiral cyclohexenediimine backbone complex [SalcyCo(III)X] with an axial X group of poor leaving ability as the electrophile, combined with a bulky nuclephile with poor leaving ability and low coordination ability, is an ideal binary catalyst system for the copolymerization of CO(2) and a racemic aliphatic epoxide to selectively produce polycarbonates with relatively high enantioselectivity, >95% head-to-tail connectivity, and >99% carbonate linkages. A fast copolymerization of CO(2) and epoxides was observed when the concentration of the electrophile or/and the nucleophile was increased, and the number of polycarbonate chains was proportional to the concentration of the nucleophile. Electrospray ionization mass spectrometry, in combination with a kinetic study, showed that the copolymerization involved the coordination activation of the monomer by the electrophile and polymer chain growth predominately occurring in the nucleophile. Both the enantiomorphic site effect resulting from the chiral electrophile and the polymer chain end effect mainly from the bulky nucleophile cooperatively control the stereochemistry of the CO(2)/epoxide copolymerization.

A new method for intermolecular sp3-sp3 C-C bond formation between primary aliphatic alcohol and olefin by use of a RhCl(PPh3)3 (cat.)/BF3.OEt2 (2.5 equiv)/BuBr (0.5 equiv)/toluene system was first disclosed, which possessed quite significant utilities for organic synthesis, especially for that of secondary alcohols. The most significant aspect is the discovery that rhodium-catalyzed C-H bond activation of alcohols is feasible under Lewis acid-promoted conditions.

Programmed assembly strategy has been first applied to the generation of self-supported Noyori-type catalysts for asymmetric hydrogenation of ketones by spontaneous heterocoordination of bridged diphosphine and diamine ligands with Ru(II) metallic ions. The immobilized catalyst demonstrates excellent enantioselectivity and activity in the heterogeneous catalysis of the hydrogenation of aromatic ketones and can be recovered and recycled at least seven times without obvious loss of selectivity and activity.

A system for coupling catalytic radical cyclization and Ir-catalyzed hydrogen atom transfer (HAT) is described. It is essential that the HAT catalyst activates H(2) quickly and is not a hydrogenation catalyst. Vaska's complex was found to fulfill both purposes efficiently.

A catalytic enantio- and diastereoselective radical cyclization using a regiodivergent epoxide opening (REO) for radical generation is described. It is demonstrated for the first time that the diastereoselectivity of cyclizations of acyclic radicals can be controlled catalytically. Building blocks for important applications in stereoselective synthesis are readily accessed.

Six organic additives, each bearing a different number of anionic charges, were added to a large excess of cationic surfactant (dodecyltrimethylammonium bromide, DTAB). The surface-tension vs log [DTAB] plot for solutions containing DTAB/trianion = 15:1 showed an abrupt break (routinely taken as the critical micelle concentration, CMC) at 2.9 mM. This constitutes a 5-fold decrease compared with a CMC of 15 mM for pure aqueous DTAB. There is a 10-fold decrease in the break-point concentration caused by a mere 3 mol % of hexanion. Corresponding CMC values from DTAB/trianion mixtures, measured by both conductivity and diffusion NMR, gave normal values of 14 mM. The unusual discrepancy between the CMC based on surface tension and on the two "bulk" methods was attributed to saturation of the air/water interface by a DTAB/trianion complex far below the concentration at which the micelles form. Thus, the sharp break seen in surface-tension "CMC plots" need not in fact attest to actual micelle formation as is almost universally assumed in colloid chemistry.

We report a new open-framework silicogermanate SU-61 containing 26-ring channels with a low framework density. It can be seen as a crystalline analogue to the mesoporous silica MCM-41. The structure is built from the assembly of (Ge,Si)10(O,OH)28 clusters. It is the first time that silicon has been successfully introduced in the Ge10 cluster in significant amounts (21% of the tetrahedral sites). Five- and six-coordinated Ge10 clusters have previously been observed in other germanate compounds leading to either dense or open structures. In SU-61, the seven-coordinated clusters fall onto yet another underlying net, the osf net. SU-61, along with other Ge10 based frameworks, shows the versatility of the germanate system to adopt defined topologies playing on the connectivity of the clusters following the principles of net decoration and scale chemistry.