The renewable energy sources with intermittent nature call for fast development of electrical energy storage (EES) devices for practical applications. [1] Over the past decades, lithium-ion batteries (LIBs) have pervaded our daily lives, ranging from portable electronics to large-scale EES systems. [2] However, the cost of rare lithium resources involving electrical grid and large-scale storage purposes have raised widespread concerns. In this regard, sodium-ion batteries (SIBs) are highly promising to meet these demands due to that sodium is practically inexhaustible and easily accessible around the globe. [3] However, the higher standard electrochemical potential of Na + /Na (−2.71 V versus SHE) than that of Li + / Li (−3.04 versus SHE) and the larger ion radius of Na + compared with Li + (1.02 Å versus 0.76 Å) mean that SIBs possess a lower energy density, and most conventional electrode materials of LIBs are not suitable for SIBs. Hence, it is of great significance to explore advanced electrode materials that could provide satisfactory specific capacities and rapid ion diffusion kinetics. So far, the development of the cathode materials for SIBs has progressed rapidly, including layered oxides [4] and polyanionic compounds. [5] As for the anodes, although hard carbon as a hotspot has been widely studied due to its high capacity and lower voltage platform, [6] the random adsorption sites and irregular channels for Na + migration lead to a relatively poor sodium-ion diffusion. 2D transition metal chalcogenides (TMCs) have been broadly reported as a kind of promising electrode materials for both LIBs and SIBs due to their open framework and unique electrochemical properties. [7,8] Among them, WS 2 as a typical 2D TMCs has a much larger interlayer spacing of 0.62 nm and weaker van der Waals interaction, which enables fast reversible Na + diffusion and avoids terrible volume expansion during Na + intercalation/deintercalation processes. [9] However, the terrible issue of pure WS 2 anode applied in SIBs is its low intrinsic electronic conductivity, significantly limiting the specific capacity, and rate performance. [10] Generally, the electrochemical properties of materials are strongly dependent on the conductivity of electrode materials as well as the diffusion rate of Na +. Thus, the scrupulous design and rational controllable synthesis of Engineering novel electrode materials with unique architectures has a significant impact on tuning the structural/electrochemical properties for boosting the performance of secondary battery systems. Herein, starting from well-organized WS 2 nanorods, an ingenious design of a one-step method is proposed to prepare a bimetallic sulfide composite with a coaxial carbon coating layer, simply enabled by ZIF-8 introduction. Rich sulfur vacancies and WS 2 /ZnS heterojunctions can be simultaneously developed, that significantly improve ionic and electronic diffusion kinetics. In addition, a homogeneous carbon protective layer around the surface of the composite guarantees an outstandi...

Developing chemically recyclable polymers represents ag reener alternative to landfill and incineration and offers ac losed-loop strategy towardacircular materials economy.H owever,t he synthesis of chemically recyclable polymers is still plagued with certain fundamental limitations, including trade-offs between the monomersc yclizability and polymerizability,a sw ell as between polymersd epolymerizability and properties.H ere we describe the subtle O-to-S substitution, dithiolactone monomers derived from abundant feedstock a-amino acids can demonstrate appealing chemical properties different from those of dilactone,i ncluding accelerated ring closure,a ugmented kinetics polymerizability,h igh depolymerizability and selectivity,and thus constitute aunique class of polythioester materials exhibiting controlled molecular weight (up to 100.5 kDa), atactic yet high crystallinity, structurally diversity,a nd chemical recyclability.T hese polythioesters well addresses the formidable challenges of developing chemically recyclable polymers by having an unusual set of desired properties,i ncluding easy-to-make monomer from ubiquitous feedstock, and high polymerizability,c rystallinity and precise tunability of physicochemical performance,aswell as high depolymerizability and selectivity.C omputational studies explain why O-to-S modification of polymer backbone enables dovetailing desirable,but conflicting,performance into one polymer structure. Figure 1. Strategies for the synthesis of recyclablep olymers.

To study the relation between allium vegetable intake and cancer of the esophagus (EC) and stomach (SC) in Yangzhong city, which is one of the highest-risk areas for these cancers in Jiangsu province, China, a simultaneous case-referent study was conducted using histopathologically confirmed cases (EC: n = = = =81, SC: n = = = =153) and population-based referents (n = = = =234).

Ring-opening polymerization of O-carboxyanhydrides (OCAs) can furnish polyesters with a diversity of functional groups that are traditionally hard to harvest by polymerization of lactones. Typical ring-opening catalysts are subject to unavoidable racemization of most OCA monomers, which hampers the synthesis of highly isotactic crystalline polymers. Here, we describe an effective bifunctional single-molecule organocatalysis for selective ring-opening polymerization of OCAs without epimerization. The close vicinity of both activating groups in the same molecule engenders an amplified synergetic effect and thus allows for the use of mild bases, thereby leading to minimal epimerization for polymerization. Ring-opening polymerization of manOCA monomer (OCA from mandelic acid) mediated by the bifunctional single-molecule organocatalyst yields highly isotactic poly­(mandelic acid) (PMA) with controlled molecular weights (up to 19.8 kg mol–1). Mixing of the two enantiomers of PMA generates the first example of a crystalline stereocomplex in this area, which displayed distinct T m values around 150 °C. Remarkably, the bifunctional catalysts are moisture-stable, recyclable, and easy to use, allowing sustainable and scalable synthesis of a stereoregular functional polyester.