Prospective Cohort Study

Energy production and storage have become key issues concerning our welfare in daily life. Present challenges for batteries are twofold. In the first place, the increasing demand for powering systems of portable electronic devices and zero-emission vehicles stimulates research towards high energy and high voltage systems. In the second place, low cost batteries are required in order to advance towards smart electric grids that integrate discontinuous energy flow from renewable sources, optimizing the performance of clean energy sources. Na-ion batteries can be the key for the second point, because of the huge availability of sodium, its low price and the similarity of both Li and Na insertion chemistries. In spite of the lower energy density and voltage of Na-ion based technologies, they can be focused on applications where the weight and footprint requirement is less drastic, such as electrical grid storage. Much work has to be done in the field of Na-ion in order to catch up with Li-ion technology. Cathodic and anodic materials must be optimized, and new electrolytes will be the key point for Na-ion success. This review will gather the up-to-date knowledge about Na-ion battery materials, with the aim of providing a wide view of the systems that have already been explored and a starting point for the new research on this battery technology.

Na-ion batteries, recent advances and present challenges to become low cost energy storage systems

The General Utility Lattice Program (GULP) has been extended to include the ability to simulate polymers and surfaces, as well as adding many other new features, and the current status of the program is fully documented. Both the background theory is described, as well as providing a concise review of some of the previous applications in order to demonstrate the range of its use. Examples are presented of work performed using the new compatibilities of the software, including the calculation of Born effective charges, mechanical properties as a function of applied pressure, calculation of frequency-dependent dielectric data, surface reconstructions of calcite and the performance of a linear-scaling algorithm for bond-order potentials.

The general utility lattice program (GULP)

Although known since the late 19th century, organic–inorganic perovskites have recently received extraordinary research community attention because of their unique physical properties, which make them promising candidates for application in photovoltaic (PV) and related optoelectronic devices. This review will explore beyond the current focus on three-dimensional (3-D) lead(II) halide perovskites, to highlight the great chemical flexibility and outstanding potential of the broader class of 3-D and lower dimensional organic-based perovskite family for electronic, optical, and energy-based applications as well as fundamental research. The concept of a multifunctional organic–inorganic hybrid, in which the organic and inorganic structural components provide intentional, unique, and hopefully synergistic features to the compound, represents an important contemporary target.

Organic–Inorganic Perovskites: Structural Versatility for Functional Materials Design

Synthesis, properties, and applications of magnetic iron oxide nanoparticles

A structural transition at 158 °C in Na0.63CoO2 is associated with a resistivity anomaly. Raman spectroscopy suggests a change in Na ordering at the transition and, for the first time, we have identified the nature of this rearrangement using variable temperature neutron powder diffraction. On heating, some Na ions migrate to the thermodynamically less stable (Na1) site from Na2, consistent with loss of an incommensurate superstructure. It is suggested that the change in Na order is linked to a change in the electronic band structure, which is reflected in the resistivity anomaly.

A linked structural and electronic transition in Na0.63CoO2

Fluorination of the n = 2 Ruddlesden–Popper phase La2BaFe2O7 occurs at ∼300 °C in flowing 10% F2 in N2 to form La2BaFe2O5F4. This oxide fluoride contains 2F− ions in interstitial sites within the rocksalt regions and 2F− ions that have substituted for O2− ions in apical sites within the rocksalt layers. The fluorination results in an expansion along c of 7.6% to yield a tetragonal unit cell of dimensions a = 3.96237(7) A, c = 22.3972(5) A. The structure and magnetic properties have been examined by Mossbauer spectroscopy, neutron powder diffraction and magnetic susceptibility measurements. La2BaFe2O5F4 becomes antiferromagnetically ordered at temperatures below ∼500 K, and the magnetic order shows a striking resemblance to that observed in La2BaFe2O7. The magnetic moments on Fe3+ are perpendicular to [001] and aligned along ±{100} directions above 300 K, but at temperatures below 200 K, they rotate by 45° to lie along ±{110}. Mossbauer spectroscopy suggests the presence of Fe3+ within the primary phase, but also indicates that fluorination results in some particle fragmentation to form a paramagnetic component of the fluorinated material.

Fluorine insertion into the Ruddlesden–Popper phase La2BaFe2O7: the structure and magnetic properties of La2BaFe2O5F4

Magnetic structure of Fe3GaAs

http://pure-oai.bham.ac.uk/ws/files/16369293/Hervoches_Variable_temperature_neutron_Solid_State_Ionics_2014.pdf

Variable temperature neutron diffraction study of crystal structure and transport pathways in oxide ion conductors Bi12.5Ln1.5ReO24.5 (Ln=Lu, Er)

A Rietveld refinement of the magnetic and nuclear structures of the CMR material Fe05Cu05Cr2S4 is presented Several unusual structural features are discussed and the structures obtained are compared to those of FeCr2S4

Colin Greaves

Papers

A linked structural and electronic transition in Na0.63CoO2

Fluorine insertion into the Ruddlesden–Popper phase La2BaFe2O7: the structure and magnetic properties of La2BaFe2O5F4

Magnetic structure of Fe3GaAs

Variable temperature neutron diffraction study of crystal structure and transport pathways in oxide ion conductors Bi12.5Ln1.5ReO24.5 (Ln=Lu, Er)

Magnetic and nuclear structures of Fe0.5Cu0.5Cr2S4 and FeCr2S4