Since the pioneering work of Goodenough and co-workers, [ 1 ] olivine-structured lithium iron phosphate (LiFePO 4 ) has been extensively studied as a cathode material for lithium-ion batteries (LIBs) for on-board energy storage in electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs), [ 2 ] as well as for stationary energy storage for wind and solar energy. [ 3 ] These studies originate from its numerous appealing advantages, such as intrinsic thermal stability, environmental benignity, low cost, and high theoretical capacity (170 mA h g − 1 ). [ 4 ] However, its insulating nature and sluggish kinetics of both electron and lithium-ion transport seriously limit its high-rate and lowtemperature properties, which are precisely the requirements for these types of applications. [ 5 ] In the past decade, tremendous efforts have been made to improve its electrochemical performance by decreasing the size of the primary particles, [ 6 ] coating with electronically conductive materials, [ 4c , 7 ] doping with foreign atoms, [ 5b , 8 ] and, recently, by constructing a three-dimensional conducting network [ 9 ] and coating with poorly crystallized pyrophosphate. [ 10 ] Among all these methods, carbonaceous materials [ 7f , 9b , 11 ] have been recognized as one of the preferred materials for wiring the surface of LiFePO 4 particles and hence enhancing their electrochemical performance. However, the introduced carbon in the LiFePO 4 /C composites is usually amorphous because of the poor graphitization ability of the precursors at the sintering temperature during formation of the pure olivine phase, making it very diffi cult to increase the rate performance of the LiFePO 4 cathode material to an ultrahigh level ( > 60 C), [ 7a , 12 ] which is extremely important to power EVs and PHEVs and store wind and solar energy. [ 10 ] In this communication, we discuss the design and preparation of a double nano-carbon (amorphous carbon coating and graphitized conducting carbon) decorated LiFePO 4 nanocomposite that can achieve ultrahigh rate capability (about 59% capacity retention at rates up to 120 C) and superior lowtemperature performance (about 71.4% capacity retention when discharged at − 25 ° C) when used as LiFePO 4 cathode material. Hereafter, for simplifi cation, we abbreviate the present double nano-carbon decorated LiFePO 4 nanocomposite as LFP@C/CNT nanocomposite, in which LFP, C and CNT represent the LiFePO 4 nanoparticles, amorphous carbon coating, and graphitized conducting carbon (carbon nanotubes, CNTs), respectively. Figure 1a shows the X-ray diffraction (XRD) pattern of the asobtained LFP@C/CNT nanocomposite. In addition to the weak diffraction peak at about 26.4 ° for multiwalled CNTs, all intense peaks in the spectrum can be well indexed to orthorhombic LiFePO 4 (JCPDS Card No. 40-1499, space group Pmnb(62) , a 0 = 6.018 Å, b 0 = 10.34 Å, c 0 = 4.703 Å), indicating the high phase purity of the LFP@C/CNT nanocomposite. The mean crystallite size of LiFePO 4 is ca. 90 nm, as estimated from the widt...

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Reverse electrodialysis (RED) or blue energy is a non-polluting, sustainable technology for generating power from the mixing of solutions with different salinity, that is, seawater and river water. A concentrated salt solution (e.g., seawater) and a diluted salt solution (e.g., river water) are brought into contact through an alternating series of polymeric anion-exchange membranes (AEMs) and cation-exchange membranes (CEMs), which are either selective for anions or cations. Currently available ion-exchange membranes are not optimized for RED, whereas successful RED operation notably depends on the used ion-exchange membranes. We designed such ion-exchange membranes and for the first time we show the performance of tailor-made membranes in RED. More specifically, we focus on the development of AEMs because these are much more complex to prepare. Herein we propose a safe and more environmentally friendly method and use halogenated polyethers, such as polyepichlorohydrin (PECH) as the starting material. A tertiary diamine (1,4-diazabicyclo[2.2.2]octane, DABCO) was used to introduce the ion-exchange groups by amination and for simultaneous cross-linking of the polymer membrane. Area resistances of the series of membranes ranged from 0.82 to 2.05 Ω cm² and permselectivities from 87 to 90 %. For the first time we showed that tailor-made ion-exchange membranes can be applied in RED. Depending on the properties and especially membrane thickness, application of these membranes in RED resulted in a high power density of 1.27 W m⁻², which exceeds the power output obtained with the commercially available AMX membranes. This shows the potential of the design of ion-exchange membranes for a viable blue energy process.

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In order to analyze and compare the phenolic characteristics of red wine grapes with diverse genetic backgrounds, skin phenolics among 21 different cultivars belonging to Vitis vinifera L., East Asian and North American Vitis species and hybrids, as well as 2 varieties of muscadine grapes were estimated by HPLC-MS/MS. There were 45 anthocyanins, 28 flavonols, 8 flavan-3-ols, 9 cinnamic acids, 5 benzoic acids, 5 ellagic acids and 2 stilbenes detected in all the samples. Total contents of each phenolic type varied significantly among the different grape cultivars investigated. There was also a large variability in the phenolic compositions of different grape groups. The differences in anthocyanin composition were obvious between V. vinifera and non-V. vinifera grapes and also between the grapes originating from Eurasia and North America. Quercetin-3-glucuronide and quercetin-3-glucoside were marker flavonol compounds for Euvitis grape skins. Flavan-3-ol monomers were dominant in the skins of muscadine and non-V. amurensis East Asian grapes, whereas polymers were more common in V. vinifera and North American grapes. The muscadine grapes were very rich in flavonols, flavan-3-ols and ellagic acids. Via principal component analysis, these grape cultivars were clustered into three groups according to their characteristic phenolic content and composition.