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A very interesting, durable and cheap class of active intercalation cathode materials is represented by open-framework structures such as Prussian blue analogues (PBAs). Manganese hexacyanoferrate (MnHCF) with nominal formula Na2Mn[Fe(CN)6]¿zH2O, only includes abundant elements and is safely and easily synthesized. The material features high specific capacities at high potentials when compared to other PBAs [1]. A combined XAS and XRD study has demonstrated that both Fe and Mn sites are involved in the electrochemical process but a capacity fading is observed during the charge and discharge steps, due to a Jahn-Teller (J-T) effect [2]. Using energy-dependent soft x-ray microscopy [3,4] in this study we reveal and visualize the spatial distribution of the oxidation state of Mn, Fe and N at different electrode composition and after 50 cycles in a Li and in a Na battery. The high-resolution access to the metal L edge provided complementary details on the metal-ligand characteristic to the one already available by hard x-ray absorption, while the images demonstrate particles at different state of charge, likely caused by J-T-related passivations, in particular in the cycled lithiated samples. This confirms the superior stability to sodiation and provides an important support for strategies aimed to the suppression of fading.

Carboxymethylcellulose (CMC) has been proposed as a polymeric binder for electrodes in environmentally friendly Li-ion batteries. Its physical properties and interaction with Li(+) ions in water are interesting not only from the point of view of electrode preparation-processability in water is one of the main reasons for its environmental friendliness-but also for its possible application in aqueous Li-ion batteries. We combine molecular dynamics simulations and variable-time pulsed field gradient spin-echo (PFGSE) NMR spectroscopy to investigate Li(+) transport in CMC-based solutions. Both the simulations and experimental results show that, at concentrations at which Li-CMC has a gel-like consistency, the Li(+) diffusion coefficient is still very close to that in water. These Li(+) ions interact preferentially with the carboxylate groups of CMC, giving rise to a rich variety of coordination patterns. However, the diffusion of Li(+) in these systems is essentially unrestricted, with a fast, nanosecond-scale exchange of the ions between CMC and the aqueous environment.

We report the first proof of concept for a non-aqueous semi-solid flow battery (SSFB) based on Na-ion chemistry using P2-type NaxNi0.22Co0.11Mn0.66O2 and NaTi2(PO4)3 as positive and negative electrodes, respectively. This concept opens the door for developing a new low-cost type of non-aqueous semi-solid flow batteries based on the rich chemistry of Na-ion intercalating compounds.

High surface area, nanostructured, and phase-pure TiO2(B) noodles-like secondary particles were successfully synthesized by a facile one-pot synthesis, based on the hydrolysis of TiCl3 using a mixture of ethylene glycol and water at moderate temperature. The primary nanoparticles have a uniform size and are about 15 nm in diameter as determined by TEM analysis and exhibit an increased exposure of the (010) facet as indicated by XRD analysis. Unlike the electrochemical reaction with lithium, the application as sodiumion electrode material reveals substantial differences, including the initial amorphization of the TiO2(B) particles, accompanied by a partial irreversibility of the sodium storage, presumably related to sodium trapping inside the active material particles and the absence of a stable solid electrolyte interphase, as indicated by galvanostatic cycling and electrochemical impedance spectroscopy, respectively. Besides, TiO2(B)-based electrodes show a stabilized reversible capacity of about 100 mAh g−1 and a very good C rate capability.

P-type layered oxides are promising cathode materials for sodium-ion batteries and a wide variety of compounds have been investigated so far. Nevertheless, detailed studies on how to link synthesis temperature, structure and electrochemistry are still rare. Herein, we present a study on P-type NaxNi0.22Co0.11Mn0.66O2 materials, investigating the influence of synthesis temperature on their structure and electrochemical performance. The change of annealing temperature leads to various materials of different morphologies and either P3-type (700 C), P3/P2-type (750 C) or P2-type (800–900 C) structure. Galvanostatic cycling of P3-type materials revealed high initial capacities but also a high capacity fade per cycle leading to a poor long-term cycling performance. In contrast, pure P2-type NaxNi0.22Co0.11Mn0.66O2, synthesized at 800 C, exhibits lower initial capacities but a stable cycling performance, underlined by a good rate capability, high coulombic efficiencies and high average discharge capacity (117 mA h g 1) and discharge voltage (3.30 V vs. Na/Na+) for 200 cycles. Introduction The interest in layered sodium-transition metal oxides, NaxMO2 (M ¼ transition metal, Ni, Co, Mn, Fe, Cr and others) is increasing signicantly in recent years.1–8 In fact, Na-based batteries appear to be a promising alternative when energy density is not a critical issue, e.g. for large scale energy storage and low-cost applications.9 Additionally, sodium is highly abundant and homogeneously distributed in the Earth's crust and sea water and, consequently, cheap.8,10,11 However, one great advantage of Na batteries is certainly the feasible replacement of copper with aluminium current collectors since Na does not alloy with this metal.12 This could represent substantial cost and weight savings for batteries.11,13 In layered NaxMO2, Na cations can be accommodated in trigonal prismatic (P), tetrahedral (T) or octahedral (O) sites between the MO6 octahedra. P-type materials nowadays are attracting interest due to their promising performance in sodium-ion batteries. Additionally, they were intensively investigated in the past due to the facile preparation of layered lithium oxides via ion-exchange.4,14–17 P2-type materials.

DIDATTICA E RICERCA NELL’UNIVERSITA ITALIANA E CONFRONTI INTERNAZIONALI Il volume raccoglie la maggior parte dei contributi che sono stati presentati e discussi il 30 e 31 maggio 2013, nel corso del primo “Seminario nazionale di biblioteconomia” organizzato, nell’ambito delle attività scientifiche del Dipartimento di Scienze documentarie, linguistico-filologiche e geografiche dell’Università di Roma La Sapienza, da Alberto Petrucciani e Giovanni Solimine, con il patrocinio della Facoltà di Lettere, dell’Associazione italiana biblioteche (AIB) e della Società italiana di scienze bibliografiche e biblioteconomiche (SISBB).

While the primary reason for nanostructuring lithium-ion active materials is commonly the realization of shorter diffusion pathways for ions and electrons, there are also other, less-expected phenomena occurring when leaving the microscale to enter the nanoscale. Herein, we will present one of these phenomena - the thermally induced fragmentation (i.e., "chopping") of oleic acid-capped anatase TiO2 nanorods perpendicular to the [001] direction. This fragmentation results in the formation of ultrafine TiO2 nanoparticles with increased (001) facets. Due to this modified surface facets ratio and the advantageous utilization of carboxymethyl cellulose as binder, these ultrafine nanoparticles present an excellent rate performance and cycling stability - even for cathodic cut-off potentials as low as 0.1 V.

The nuclear fuel cycle is the series of stages that nuclear fuel materials go through in a cradle to grave framework. The Once Through Cycle (OTC) is the current fuel cycle implemented in the United States; in which an appropriate form of the fuel is irradiated through a nuclear reactor only once before it is disposed of as waste. The discharged fuel contains materials that can be suitable for use as fuel. Thus, different types of fuel recycling technologies may be introduced in order to more fully utilize the energy potential of the fuel, or reduce the environmental impacts and proliferation concerns about the discarded fuel materials. Nuclear fuel cycle systems analysis is applied in this paper to attain a better understanding of the strengths and weaknesses of fuel cycle alternatives. Through the use of the nuclear fuel cycle analysis code CAFCA (Code for Advanced Fuel Cycle Analysis), the impact of a number of recycling technologies and the associated fuel cycle options is explored in the context of the U.S. energy scenario over 100 years. Particular focus is given to the quantification of Uranium utilization, the amount of Transuranic Material (TRU) generated and the economics of the different options compared to the base-line case, the OTC option. It is concluded that LWRs and the OTC are likely to dominate the nuclear energy supply system for the period considered due to limitations on availability of TRU to initiate recycling technologies. While the introduction of U-235 initiated fast reactors can accelerate their penetration of the nuclear energy system, their higher capital cost may lead to continued preference for the LWR-OTC cycle., Electric Power Research Institute, Idaho National Laboratory, Nuclear Energy Institute

A concentrating solar power system is presented which uses hillside mounted heliostats to direct sunlight into a volumetric absorption molten salt receiver with integral storage. The concentrated sunlight penetrates and is absorbed by molten salt in the receiver through a depth of 4–5 m, making the system insensitive to the passage of clouds. The receiver volume also acts as the thermal storage volume eliminating the need for secondary hot and cold salt storage tanks. A small aperture and refractory-lined domed roof reduce losses to the environment and reflect thermal radiation back into the pond. Hot salt is pumped from the top of the tank through a steam generator and then returned to the bottom of the tank. An insulated barrier plate is positioned within the tank to provide a physical and thermal barrier between the thermally stratified layers, maintaining hot and cold salt volumes required for continuous operation. As a result, high temperature thermal energy can be provided 24/7 or at any desired time. The amount of storage required depends on local needs and economic conditions. About 2500 m[superscript 3] of nitrate salt is needed to operate a 4 MW[subscript e] steam turbine 24/7 (7 h sunshine, 17 h storage), and with modest heliostat field oversizing to accumulate energy, the system could operate for an additional 24 h (1 cloudy day). Alternatively, this same storage volume can supply a 50 MWe turbine for 3.25 h without additional solar input. Cosine effect losses associated with hillside heliostats beaming light downwards to the receiver are offset by the elimination of a tower and separate hot and cold storage tanks and their associated pumping systems. Reduced system complexity also reduces variable costs. Using the NREL Solar Advisor program, the system is estimated to realize cost-competitive levelized production costs of electricity., Bill & Melinda Gates Foundation (Fellowship), Chesonis Family Foundation (Fellowship)