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The design of Faradaic battery electrodes with high rate capability and long cycle life comparable to those of supercapacitors is a grand challenge. Here, we bridge this performance gap by taking advantage of a unique ultrafast proton conduction mechanism in vanadium oxide electrode, developing an aqueous battery with untrahigh rate capability up to 1000 C (400 A g −1 ) and extremely long life of 0.2 million cycles. The mechanism is elucidated by comprehensive experimental and theoretical results. Instead of slow individual Zn 2+ transfer or Grotthuss chain transfer of confined H + , the ultrafast kinetics and excellent cyclic stability are enabled by rapid 3D proton transfer in vanadium oxide via the special pair dance switching between Eigen and Zundel configurations with little constraint and low energy barriers. This work provides insight into developing high-power and long-life electrochemical energy storage devices with nonmetal ion transfer through special pair dance topochemistry dictated by hydrogen bond.

A core feature of covalent organic frameworks (COFs) is crystallinity, but current crystallization processes rely substantially on trial and error, chemical intuition and large-scale screening, which typically require harsh conditions and low levels of supersaturation, hampering the controlled synthesis of single-crystal COFs, particularly on large scales. Here we report a strategy to produce single-crystal imine-linked COFs in aqueous solutions under ambient conditions using amphiphilic amino-acid derivatives with long hydrophobic chains. We propose that these amphiphilic molecules self-assemble into micelles that serve as dynamic barriers to separate monomers in aqueous solution (nodes) and hydrophobic compartments of the micelles (linkers), thereby regulating the polymerization and crystallization processes. Disordered polyimines were obtained in the micelle, which were then converted into crystals in a step-by-step fashion. Five different three-dimensional COFs and a two-dimensional COF were obtained as single crystals on the gram scale, with yields of 92% and above. © 2023. The Author(s), under exclusive licence to Springer Nature Limited.

Living organisms explored functional biomolecules such as proteins bearing glycine to create single-crystals of minerals in water without resorting to low levels of supersaturation. However, this strategy remains poorly effective in the crystallization of organic polymers. Here, we report a biomimetic strategy and its implementation to synthesize single-crystals of an important class of organic polymers - covalent organic frameworks (COFs) in water under ambient conditions. The strategy explores assemblies of amphiphilic molecules of glycine derivatives as dynamic barriers to separate monomers in water and oil phases, thereby regulating the polymerization and crystallization processes. Monomers first polymerized into disordered solids regardless of concentration variations over five orders of magnitude, then transformed into crystals in a step-by-step fashion with monomers and dimers as main building units, affording six types of single-crystals at the gram-scale with yields of ≥ 92% besides a two-dimensional COF-366. This study will be a valuable addition to the repertoire of crystallization path and methodology of organic polymers and promote their industrial applications.

Harvesting solar energy for water desalination is one of the most promising ways to produce clean water. Because of the absorber detachment and base material degradation, the solar steam generator still suffers from drastic energy loss even when using absorber materials with high photothermal conversion efficiency. We herein propose a practical desalination design that can maintain both the working efficiency and operating life. This device is made from the Paulownia wood covalently bonded with MXene on the top. Paulownia wood, as a natural heat insulator, servers as an excellent transport and customized evaporator. This heat absorber-Paulownia wood system achieved an evaporation rate of 1.465 kg m

Platinum-based (Pt-based) catalysts are considered as the most effective electrocatalysts for the hydrogen evolution reaction (HER). Because of the high cost, it is essential to improve the mass ac...

Cyclic oligocarboxylic acids are the most commonly explored phosphate-free inhibitors for calcium carbonate scale deposition. The structural chemistry of calcium complexes of candidate inhibitors has the potential to give insight into inhibitor mode of action and design. We report a series of calcium compounds of cyclic oligocarboxylic acids of (1α,3α,5α)-1,3,5,-cyclohexanetricarboxylic acid (CHTCA); cyclohexane-1,2,4,5-tetracarboxylic acid (CHTTCA); 1,2,3,4,5,6-cyclohexanehexacarboxylic acid (CHHCA); 1,1-cyclohexandiacetic acid (CHDAA) and cis,cis,cis,cis-1,2,3,4-cyclopentanetetracarboxylic acid (CPTCA) to understand the relationship between ligand stereochemistry and calcium ion coordination mode.

Layered lithium cobalt oxide (LiCoO2, LCO) is the most successful commercial cathode material in lithium-ion batteries. However, its notable structural instability at potentials higher than 4.35 V (versus Li/Li+) constitutes the major barrier to accessing its theoretical capacity of 274 mAh g−1. Although a few high-voltage LCO (H-LCO) materials have been discovered and commercialized, the structural origin of their stability has remained difficult to identify. Here, using a three-dimensional continuous rotation electron diffraction method assisted by auxiliary high-resolution transmission electron microscopy, we investigate the structural differences at the atomistic level between two commercial LCO materials: a normal LCO (N-LCO) and a H-LCO. These powerful tools reveal that the curvature of the cobalt oxide layers occurring near the surface dictates the structural stability of the material at high potentials and, in turn, the electrochemical performances. Backed up by theoretical calculations, this atomistic understanding of the structure–performance relationship for layered LCO materials provides useful guidelines for future design of new cathode materials with superior structural stability at high voltages. A three-dimensional continuous rotation electron diffraction method allows atomistic characterization of the chemistry of curved layered cathode materials.

This paper reports the characterization of the composition and morphology of mineral formation on glass and plastic (polymethylmethacrylate) substrates in a dishwasher environment and the identification of suitable phosphate-free mineral crystallization inhibitors as environmentally benign candidates to replace the currently used phosphate-containing inhibitor 1-hydroxyethane 1,1-diphosphoric acid (HEDP). Screening of the calcium carbonate crystallization inhibition performance of twenty-eight different compounds resulted in the identification of two phosphate-free, cyclic polycarboxylic acid inhibitors, which were found in combination to be effective replacements. Each inhibitor proved to be highly substrate specific with all-cis-cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) preventing deposition on glass (where calcite is the dominant polymorph) and cis,cis,cis,cis-cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA) inhibiting aragonite deposition on polymethylmethacrylate (PMMA). When used in combination, these two species prevented all forms of calcium carbonate deposition on both substrate types. The underlying inhibition mechanism and structural requirements of an efficient calcium carbonate inhibitor are also discussed.

Nitrogen dioxide (NO2) is a toxic air pollutant, and efficient abatement technologies are important to mitigate the many associated health and environmental problems. Here, we report the reactive adsorption of NO2 in a redox-active metal-organic framework (MOF), MFM-300(V). Adsorption of NO2 induces the oxidation of V(III) to V(IV) centers in MFM-300(V), and this is accompanied by the reduction of adsorbed NO2 to NO and the release of water via deprotonation of the framework hydroxyl groups, as confirmed by synchrotron X-ray diffraction and various experimental techniques. The efficient packing of NO2 center dot N2O4(infinity) chains in the pores of MFM-300(V-IV) results in a high isothermal NO2 uptake of 13.0 mmol g(-1) at 298 K and 1.0 bar and is retained for multiple adsorption-desorption cycles. This work will inspire the design of redox-active sorbents that exhibit reductive adsorption of NO2 for the elimination of air pollutants.

A series of platinum based low-molecular-weight urea-based gelators C1, C2, and C3, mimicking the structure of the anticancer drug cisplatin has been synthesized, as part of the development of a targeted, supramolecular gel phase crystallization and polymorphism screening strategy. Morphological and rheological studies established that inclusion of a longer spacer between the urea and cisplatin-mimetic regions of the gelator (C3) resulted in optimal gelation performance. Interfacial crystallization of cisplatin in a gel–sol biphasic system has been employed to address the insolubility of the drug molecule in organic solvents. A new N,N-dimethylacetamide (DMA) solvate of cisplatin has been identified and a crystal habit modification of the known N,N-dimethylformamide (DMF) solvate form of cisplatin has been observed on crystallization of cisplatin in C3 gels prepared in xylenes. While both targeted and nontargeted gels resulted in the formation of the new DMA solvate, only the targeted C3 gel resulted in high-quality single crystal suitable for characterization by single crystal crystallography. The high crystal quality is attributed to a close match between the core geometry of C3 with that of cisplatin together with local order in the gel fibers of C3.