Science China Chemistry最新文献

Aqueous zinc-ion batteries (ZIBs) have attracted much interest to realize safe rechargeable batteries with high safety and high energy density. However, it is still challenging to address dendrite growth and parasitic reactions in zinc anodes. We propose herein the design concept of hydrogen bond-induced elastic polyzwitterion electrolytes with zincophilic groups for achieving robust ZIBs. Mussel-inspired autopolymerization has been developed to construct the polyzwitterion electrolytes at room temperature by inducing electron density delocalization at α-position of C=C bond in zwitterion monomer by Zn²⁺. Specifically, the zwitterionic functional groups construct ion transport channels, and the unique–NH–and SO₃⁻ groups co-compete with H₂O for coordination with Zn²⁺ and promote the desolvation of hydrated Zn²⁺, thus achieving a high room temperature ionic conductivity (6.7 mS cm⁻¹) and an increased Zn²⁺ migration number (0.65) for the polyzwitterion electrolytes. In addition, various interactions such as hydrogen bonding and electrostatic interactions between electrolyte ions and zwitterionic groups impart high stretchability and strength to the polyzwitterion electrolytes, which, combined with SO₃⁻ philic (002) crystallographic properties, effectively inhibit the growth of zinc dendrites. As a result, rigid/wearable solid-state ZIBs exhibit excellent cycling and C-rate performances. We believe that the strategy of constructing polyzwitterionic electrolytes with zincophilic groups and ion transport channels opens up a new direction in polymer electrolyte engineering towards safe and high energy batteries.

Tandem hydroformylation/hydrogenation of olefins to alcohols is an appealing and challenging route that has received continuous interest. Herein, we report a bifunctional atomically dispersed Rh and Co catalyst (RhCo/Al₂O₃-10) prepared by a simple ball milling method that displays superior synergistic catalytic performance (>95% olefins conversion and >80% alcohols selectivity) and broad substrate scope for tandem hydroformylation/hydrogenation reaction, outperforming Rh/Al₂O₃, Co/Al₂O₃, and their physically mixed counterparts. In situ CO-DRIFTS, XPS, and kinetic experiments demonstrate that the electron interaction between Rh and Co atoms effectively lowers the apparent activation energy, thus promoting the tandem hydroformylation/hydrogenation reaction. This work not only presents a novel tandem hydroformylation/hydrogenation reaction system for converting olefins to alcohol but also throws light on the rational design of versatile bifunctional catalysts for on-demand synergistic catalysis.

Developing highly stable electrocatalysts under industry-compatible current densities (>500 mA cm⁻²) in an anion-exchange membrane water electrolyzer (AEMWE) is an enormous challenge for water splitting. Herein, based on the results of density function theory calculations, a dual heterogeneous interfacial structured NiSe/Fe-Ni(OH)₂ catalyst was subtly designed and successfully prepared by electrodepositing Fe-doped Ni(OH)₂ on NiSe-loaded nickel foam (NF). Fe doping-driven heterogeneous structures in NiSe/Fe-Ni(OH)₂ markedly boost catalytic activity and durability at industrially compatible current densities in single hydrogen and oxygen evolution reactions under alkaline conditions. In particular, NiSe/Fe-Ni(OH)₂ shows a negligible performance loss at 600 mA cm⁻² at least 1,000 h for overall water splitting, a distinguished long-term durability acting as AEMWE electrodes at 600 mA cm⁻² and 1 A cm⁻² at 85 °C for at least 95 h. Owing to Fe doping-induced strong synergetic effect between Ni and Fe, dual heterostructure-promoted charge transfer and redistribution, abundant catalytic active sites, and improvement of stability and durability, a mechanism of Fe doping-driven heterogeneous interfacial structure-promoted catalytic performance was proposed. This study provides a successful example of theory-directed catalyst preparation and pioneers a creative strategy for industry-compatible water splitting at high current density.

Despite the recent advances in the selective functionalization of C–C bonds in specific substrates, cleavage and functionalization of C–C bonds in acyclic substrates, such as ethane derivatives, remains challenging. In contrast to the well-developed functionalization of one carbon fragment after C–C bond cleavage, herein, we report a novel electro-reductive carboxylation of C (sp³)–C(sp³) bond in multi-aryl ethanes with carbon dioxide (CO₂) by utilizing both carbon fragments. Thus, this reaction exhibits an atom-, step-economic approach for the synthesis of carboxylic acids, fulfilling principal aspirations of organic synthesis. Moreover, this method features mild reaction conditions, broad substrate scope, and good functional group tolerance. Symmetric and asymmetric substrates bearing primary, secondary, or tertiary C(sp³)–C(sp³) bonds are all amenable to this strategy, enabling one or two structurally different carboxylic acids to be facilely constructed at the same time. Mechanistic investigations indicate that carbanions might be the key intermediates in this reaction, which could be captured by CO₂ efficiently.

N-Hydroxyphthalimide (NHPI) esters have emerged as powerful sources of alkyl radicals generated by single-electron transfer, but homolysis of NHPI ester to produce an alkyl radical and a phthalimide nitrogen radical is still in its infancy. In this study, we developed a light-induced method for generation of alkyl and phthalimide nitrogen radicals from NHPI esters and subsequent reactions of the radicals with [1.1.1]propellane and aryl aldehydes for rapid generation of bicycle [1.1.1]pentane ketones. This method does not require metals or photosensitizers, features a broad substrate scope (90 examples) and excellent functional group tolerance, and can be used for the functionalization of structurally complex natural products and drugs. Mechanistic investigations indicate that the reaction involves photoinduced homolytic cleavage of the Cs₂CO₃-NHPI ester complex to produce alkyl and phthalimide nitrogen radicals and subsequent hydrogen atom transfer between the phthalimide nitrogen radical and the aldehyde to generate an acyl radical.

Metal-organic frameworks (MOFs) and their derivatives received more and more attention due to the diverse morphologies, rich porous structures, and tunable metal active sites, which have been widely used in energy-related electrocatalytic reactions. Surfactants, a class of compounds with hydrophilic and hydrophobic portions in the molecular structure, are able to modulate the properties of liquid and solid surfaces. Surfactants play a crucial role in controlling the shape and size of MOFs, which helps optimize electrocatalytic performance, especially in improving the exposure and accessibility of catalytic active sites. In this review, we first outline the types and applications of surfactants. Second, we describe the interface modulation and reaction mechanism of different surfactants during the forming of MOFs and their derivatives. Finally, we discuss the current applications of surfactant-modified MOFs and their derivatives in electrocatalysis. This review provides a better understanding of surfactant-assistant structure regulation and electrocatalytic activity study of MOFs and their derivatives.