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Comprehensive Summary: The merits of intrinsic electrical conductivity, high specific surface area, tunable chemical composition and tailor‐made properties enable two‐dimensional conductive metal‐organic frameworks (2D c‐MOFs) as promising next‐generation electrode materials in the field of energy storage and conversion. Herein, we have designed and synthesized a novel pyrazine‐based 2D c‐MOF (TPQG‐Cu‐MOF) bearing extended π‐conjugated structure and abundant redox active sites. Thanks to the excellent redox reversibility of pyrazine units and CuO2 units, as well as the insolubility of the rigid framework skeleton, TPQG‐Cu‐MOF as the cathode material of lithium‐ion battery exhibits a reversible specific capacity (150.2 mAh·g–1 at 20 mAh·g–1), good cycling stability (capacity retention of 82.6% after 500 cycles at 1 A·g–1) and excellent rate performance. Comprehensive ex‐situ spectroscopic studies revealed the reversible redox activity of pyrazine units and CuO2 units of TPQG‐Cu‐MOF during the Li+ insertion/extraction process. The deepening fundamental understanding of the structure‐property relationship was proposed, which might pave the way for further development of efficient MOF‐based energy storage devices. [ABSTRACT FROM AUTHOR]

Solid‐electrolyte interphase (SEI) seriously affects battery's cycling life, especially for high‐capacity anode due to excessive electrolyte decomposition from particle fracture. Herein, we report an ultrathin SEI (3–4 nm) induced by Cu+‐tailored double electrical layer (EDL) to suppress electrolyte consumption and enhance cycling stability of CuS anode in sodium‐ion batteries. Unique EDL with SO3CF3‐Cu complex absorbing on CuS in NaSO3CF3/diglyme electrolyte is demonstrated by in situ surface‐enhanced Raman, Cyro‐TEM and theoretical calculation, in which SO3CF3‐Cu could be reduced to CuF2‐rich SEI. Dispersed CuF2 and F‐containing compound can provide good interfacial contact for formation of ultrathin and stable SEI film to minimize electrolyte consumption and reduce activation energy of Na+ transport. As a result, the modified CuS delivers high capacity of 402.8 mAh g−1 after 7000 cycles without capacity decay. The insights of SEI construction pave a way for high‐stability electrode. [ABSTRACT FROM AUTHOR]

The fundamental challenges that coexisted around sulfur cathode energy storage systems, are the severe polysulfide dissolution and low reactivity resulting in poor reversibility and short cycle life, specifically, in inexpensive sodium ion batteries. Herein, the solution‐processed synthesis of ultra‐high intimate contacted FeS2/S architecture is reported and evolution of the dynamic multistage coupling between the FeS2 and S in sodium–sulfur batteries is revealed. Atomic visualization and in situ spectroscopy conclude that: NaxFeS2 (0

Abstract Background Rates of synonymous nucleotide substitutions are, in general, exceptionally low in plant mitochondrial genomes, several times lower than in chloroplast genomes, 10–20 times lower than in plant nuclear genomes, and 50–100 times lower than in many animal mitochondrial genomes. Several cases of moderate variation in mitochondrial substitution rates have been reported in plants, but these mostly involve correlated changes in chloroplast and/or nuclear substitution rates and are therefore thought to reflect whole-organism forces rather than ones impinging directly on the mitochondrial mutation rate. Only a single case of extensive, mitochondrial-specific rate changes has been described, in the angiosperm genus Plantago. Results We explored a second potential case of highly accelerated mitochondrial sequence evolution in plants. This case was first suggested by relatively poor hybridization of mitochondrial gene probes to DNA of Pelargonium hortorum (the common geranium). We found that all eight mitochondrial genes sequenced from P. hortorum are exceptionally divergent, whereas chloroplast and nuclear divergence is unexceptional in P. hortorum. Two mitochondrial genes were sequenced from a broad range of taxa of variable relatedness to P. hortorum, and absolute rates of mitochondrial synonymous substitutions were calculated on each branch of a phylogenetic tree of these taxa. We infer one major, ~10-fold increase in the mitochondrial synonymous substitution rate at the base of the Pelargonium family Geraniaceae, and a subsequent ~10-fold rate increase early in the evolution of Pelargonium. We also infer several moderate to major rate decreases following these initial rate increases, such that the mitochondrial substitution rate has returned to normally low levels in many members of the Geraniaceae. Finally, we find unusually little RNA editing of Geraniaceae mitochondrial genes, suggesting high levels of retroprocessing in their history. Conclusion The existence of major, mitochondrial-specific changes in rates of synonymous substitutions in the Geraniaceae implies major and reversible underlying changes in the mitochondrial mutation rate in this family. Together with the recent report of a similar pattern of rate heterogeneity in Plantago, these findings indicate that the mitochondrial mutation rate is a more plastic character in plants than previously realized. Many molecular factors could be responsible for these dramatic changes in the mitochondrial mutation rate, including nuclear gene mutations affecting the fidelity and efficacy of mitochondrial DNA replication and/or repair and – consistent with the lack of RNA editing – exceptionally high levels of "mutagenic" retroprocessing. That the mitochondrial mutation rate has returned to normally low levels in many Geraniaceae raises the possibility that, akin to the ephemerality of mutator strains in bacteria, selection favors a low mutation rate in plant mitochondria.

SnO2/graphene materials have received extensive attention in broad applications owning to their excellent performances. However, multi-step and harsh synthetic methods with high temperatures and high pressures are major obstacles that need to be overcome. Herein a simple, low-cost, and scalable approach is proposed to construct ultrafine SnO2/graphene nanomaterials effectively under constant pressure and at the low temperature of 80 °C for 4 h, in which ultrafine SnO2 nanoparticles grow on graphene sheets uniformly and firmly via Sn–O–C bonding. This result depends on the synergetic effect of two reactions, the reduction of graphene oxide and formation of SnO2 nanoparticles, which are achieved successfully. More importantly, the constructed SnO2/graphene material exhibits excellent electrochemical properties in both lithium-ion batteries and sodium-ion batteries. As an anode material for lithium-ion batteries, it displays a high reversible capacity (1420 mA h g−1 at 0.1 A g−1 after 90 cycles) and good cycling life (97% at 1 A g−1 after 230 cycles), whereas in sodium-ion batteries, it maintains a capacity of 1280 mA h g−1 at 0.05 A g−1 and 650 mA h g−1 at 0.2 A g−1 after 90 cycles. The proposed synthetic methodology paves the way for the effective and large scale preparation of graphene-based composites for broad applications such as energy storage, optoelectronic devices, and catalysis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The merits of intrinsic electrical conductivity, high specific surface area, tunable chemical composition and tailor‐made properties enable two‐dimensional conductive metal‐organic frameworks (2D c‐MOFs) as promising next‐generation electrode materials in the field of energy storage and conversion. Herein, we have designed and synthesized a novel pyrazine‐based 2D c‐MOF (TPQG‐Cu‐MOF) bearing extended π‐conjugated structure and abundant redox active sites. Thanks to the excellent redox reversibility of pyrazine units and CuO2 units, as well as the insolubility of the rigid framework skeleton, TPQG‐Cu‐MOF as the cathode material of lithium‐ion battery exhibits a reversible specific capacity (150.2 mAh·g–1 at 20 mAh·g–1), good cycling stability (capacity retention of 82.6% after 500 cycles at 1 A·g–1) and excellent rate performance. Comprehensive ex‐situ spectroscopic studies revealed the reversible redox activity of pyrazine units and CuO2 units of TPQG‐Cu‐MOF during the Li+ insertion/extraction process. The deepening fundamental understanding of the structure‐property relationship was proposed, which might pave the way for further development of efficient MOF‐based energy storage devices. [ABSTRACT FROM AUTHOR]