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Organic electrode materials are promising alternatives to transition-metal based intercalation compounds for the next generation of high-performance and sustainable batteries. Herein, a novel quinone-based organic, lithium salt of poly(2,5-dihydroxy-p-benzoquinonyl sulfide) (Li 2 PDHBQS), was successfully synthesized through a simple one-step polycondensation reaction, and applied as a cathode for Li-organic batteries. As an oligomeric lithium salt with average polymerization degree of 7, Li 2 PDHBQS combines the advantages of the O/Li/O coordination bond and increased molecular weight, thus solves absolutely the dissolution problem of active material in non-aqueous electrolytes, which has seriously hindered development of organic electrode materials. Benefiting from the high theoretical capacity, intrinsic insolubility, fast reaction kinetics of the quinone group, accelerated Li-ion transport and uniform blending with conductive carbon, as well as the stable amorphous structure, Li 2 PDHBQS shows superior comprehensive electrochemical performance including high reversible capacity (268 mA h g À1 ), high cycling stability (1500 cycles, 90%), high rate capability (5000 mA g À1 , 83%) andhigh Coulombic efficiency (99.9-100.1%). Investigation of the structure-property relationship of Li 2 PDHBQS and its analogues also gives new insights into developing novel quinone-based organic electrode materials, for building better Li-organic or Na-organic batteries beyond traditional Li-ion batteries. Broader contextAll electroactive organics or polymers involving reversible redox reactions have the potential to be applied as organic electrode materials for rechargeable batteries. Aer nearly half a century's exploration, conjugated carbonyl compounds are recognized as one of the most promising types among various electroactive materials, as only they have the potential to achieve simultaneously high energy density, high cycling stability and high power density. The conjugated carbonyl compounds can be divided into small organic molecules, organic polymers and organic salts according to the molecular structure, or quinones, dianhydrides, carboxylates, diketones and so on according to the electroactive group. Usually the redox potential of conjugated carbonyl compounds is between 1.5 and 3.0 V vs. Li + /Li, but carboxylates show relatively low redox potential below 1.0 V vs. Li + /Li, so they have the potential to be applied as either cathode or anode. As the theoretical specic capacity is up to 600 mA h g À1 , it is possible to achieve high energy density, although the redox potential is much lower than that of conventional inorganic cathodes. Research on this topic mainly focuses on solving the dissolution problem of active materials to improve the cycling stability, as well as developing new organic electrode materials with higher energy density.

The cover picture shows a green and highly efficient synthetic method for the synthesis of quinazoline-2,4-diones from readily available isatins and arylamines. This method is interesting in keeping with the notion of green chemistry because of the use of hydrogen peroxide as the terminal oxidant. The rearrangement oxidation exhibited good functional group tolerability, metal-free catalysts, obviating the need for oxidants and only environmentally benign H 2 O was released. Moreover, an antibacterial activity study was performed to evaluate the antimicrobial activities. The results showed that some of the testing compounds inhibited the growth of the Staphylococcus aureus (32 μg/mL) and Staphylococcus epidermidis (64 μg/mL), which could potentially solve the problem of multidrug resistance. More details are discussed in the article by Shang et al. on page 1835-1843. The back cover picture shows X-ray near edge absorption spectroscopy has been applied to cathode materials for lithium ion batteries to explore its structure-activity relationship. The result shows that in the Li-rich cathode Li 1.15 Ni 0.47 Sb 0.38 O 2 , as a model system, Ti ions replaced the Li ions and then made an antistructure defect. It would change our understanding to the doped method for the cathode layer materials and benefit for designing other more powerful cathodes. In the picture, the road has been represented by the curve shape of the XANES of the as-studied sample. The atomic arrangement around the Ti ion of the sample has been put into the tank position of the car. NSRL, National Synchrotron Radiation Laboratory, is the name of our laboratory. More details are discussed in the article by Chu et al. on page 1853-1860. This review presents the recent advancement of transition metal-catalyzed asymmetric fluorination reactions, in which the final C-F bond derived from reductive elimination of organometallic complexes. In addition, the perspective of the field is also provided for the future studies of asymmetric fluorinations and the related transformations. 1789 Because of large specific capacity, low and safe redox potential and low cost, Li 3 VO 4 is regarded as a promising intercalation anode material for the Li-ion batteries. Here, its structure, charge/discharge mechanism, and preparation methods are reviewed. Moreover , we focus on the understanding of its electrochemical performance and highlight the recent breakthroughs. Finally, future opportunities and challenges on this anode material are also discussed. COMMUNICATION 1808 A one-pot three-component reaction of aldehydes, nitroalkanes and NaN 3 for the synthesis of NH-1,2,3-triazoles has been developed. A novel small-molecule BODIPY-acceptor was synthesized by extending the BODIPY-diketopyrrolopyrrole excited electron delocalization through the BODIPY meso-carbon, the ideal position for BODIPY's excited electron delocalization. This BODIPY acceptor shows unprecedented broad and intense absorption (see the figure), having a dual role as the wide and narrow band gap organic acc...

Distinct from pure graphene, N-doped graphene (GN) has been found to possess high rate capability and capacity for lithium storage. However, there has still been a lack of direct experimental evidence and fundamental understanding of the storage mechanisms at the atomic scale, which may shed a new light on the reasons of the ultrafast lithium storage property and high capacity for GN. Here we report on the atomistic insights of the GN energy storage as revealed by in situ transmission electron microscopy (TEM). The lithiation process on edges and basal planes is directly visualized, the pyrrolic N "hole" defect and the perturbed solid-electrolyte-interface configurations are observed, and charge transfer states for three N-existing forms are also investigated. In situ high-resolution TEM experiments together with theoretical calculations provide a solid evidence that enlarged edge {0002} spacings and surface hole defects result in improved surface capacitive effects and thus high rate capability and the high capacity are owing to short-distance orderings at the edges during discharging and numerous surface defects; the phenomena cannot be understood previously by standard electron or X-ray diffraction analyses.