Na1.5La1.5TeO6:Na+ conduction in a novel Na-rich double perovskite

Increasing demand for lithium batteries for automotive applications, coupled with the necessity to move to large-scale energy storage systems, is driving a push towards new technologies and has seen Na-ion batteries emerge as a leading alternative to Li-ion. Amongst these, all solid-state configurations represent a promising route to achieving higher energy densities and increased safety. Remaining challenges include the need for Na+ solid electrolytes with the requisite ionic conductivities crucial for use in a solid-state cell. Here, we present the novel Na-rich double perovskite, Na1.5La1.5TeO6. The transport properties, explored at the macroscopic and local level, reveal a low activation energy barrier for Na+ diffusion and great promise for use as an electrolyte for all solid-state Na-batteries

Muon studies of Li+ diffusion in LiFePO4 nanoparticles of different polymorphs

The lithium diffusion in nanostructured olivine LiFePO4 has been investigated for the first time using muon spectroscopy (μSR). A microwave-assisted approach has been employed for nanoparticle preparation, where the choice of solvent is shown to play an important role in determining particle morphology and crystal chemistry. Two phases have been obtained: Pnma LiFePO4 and the high pressure Cmcm phase. The Li+ diffusion behaviour is strikingly different in both phases, with DLi of 6.25 × 10−10 cm2 s−1 obtained for Pnma LiFePO4 in good agreement with measurements of bulk materials. In contrast, Li+ diffusion is impeded with the addition of the high pressure Cmcm phase, with a lower DLi of 3.96 × 10−10 cm2 s−1 noted. We have demonstrated an efficient microwave route to nanoparticle synthesis of positive electrode materials and we have also shown μSR measurements to be a powerful probe of Li+ diffusion behaviour in nanoparticles

Mechanistic insights of Li+ diffusion within doped LiFePO4 from Muon Spectroscopy

The Li+ ion diffusion characteristics of V- and Nb-doped LiFePO4 were examined with respect to undoped LiFePO4 using muon spectroscopy (µSR) as a local probe. As little difference in diffusion coefficient between the pure and doped samples was observed, offering DLi values in the range 1.8–2.3 × 10−10 cm2 s−1, this implied the improvement in electrochemical performance observed within doped LiFePO4 was not a result of increased local Li+ diffusion. This unexpected observation was made possible with the µSR technique, which can measure Li+ self-diffusion within LiFePO4, and therefore negated the effect of the LiFePO4 two-phase delithiation mechanism, which has previously prevented accurate Li+ diffusion comparison between the doped and undoped materials. Therefore, the authors suggest that µSR is an excellent technique for analysing materials on a local scale to elucidate the effects of dopants on solid-state diffusion behaviour

In situ diffusion measurements of a NASICON-structured all-solid-state battery using muon spin relaxation

In situ muon spin relaxation is demonstrated as an emerging technique that can provide a volume-averaged local probe of the ionic diffusion processes occurring within electrochemical energy storage devices as a function of state of charge. Herein, we present work on the conceptually interesting NASICON-type all-solid-state battery LiM2(PO4)3, using M = Ti in the cathode, M = Zr in the electrolyte, and a Li metal anode. The pristine materials are studied individually and found to possess low ionic hopping activation energies of ∼50−60 meV and competitive Li+ self-diffusion coefficients of ∼10^–10–10^–9 cm2 s^–1 at 336 K. Lattice matching of the cathode and electrolyte crystal structures is employed for the all-solid-state battery to enhance Li+ diffusion between the components in an attempt to minimize interfacial resistance. The cell is examined by in situ muon spin relaxation, providing the first example of such ionic diffusion measurements. This technique presents an opportunity to the materials community to observe intrinsic ionic dynamics and electrochemical behavior simultaneously in a nondestructive manner

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease, is characterized by the degeneration of both upper and lower motor neurons, which leads to muscle weakness and eventual paralysis. Until recently, ALS was classified primarily within the neuromuscular domain, although new imaging and neuropathological data have indicated the involvement of the non-motor neuraxis in disease pathology. In most patients, the mechanisms underlying the development of ALS are poorly understood, although a subset of patients have familial disease and harbour mutations in genes that have various roles in neuronal function. Two possible disease-modifying therapies that can slow disease progression are available for ALS, but patient management is largely mediated by symptomatic therapies, such as the use of muscle relaxants for spasticity and speech therapy for dysarthria

Muon spectroscopy for investigating diffusion in energy storage materials

We review recent applications of positive muon spin relaxation (μSR) spectroscopy as an active probe of ion diffusion in energy storage materials. μSR spectroscopy allows the study of ionic diffusion in solid-state materials on a time scale between 10−5 and 10−8 s where most long-range and consecutive short-range jumps of ions between interstitial sites occur. μSR also allows one to probe and model ionic diffusion in materials that contain magnetic ions, since both electronic and nuclear contributions to the muon depolarization can be separated, making μSR an excellent technique for the microscopic study of the ionic motions in crystalline materials. We highlight a series of battery materials for which μSR has provided insight into intrinsic ionic conduction and magnetic properties without interference of external factors, such as the presence of magnetic ions, macroscopic particle morphologies, or elaborate measurement setups

Smooth pursuit and antisaccade eye movements in siblings discordant for schizophrenia

Smooth pursuit eye movement (SPEM) and antisaccade deficits have been proposed as endophenotypes in the search for schizophrenia genes. We assessed these measures in 24 schizophrenia patients, 24 of their healthy siblings, and 24 healthy controls closely matched to the siblings. Between-group differences were assessed using a random effects regression model taking into account the relatedness between patients and siblings. Patients showed reduced SPEM gain, increased frequency of saccades during pursuit, increased antisaccade error rate, and reduced antisaccade gain compared to controls. Siblings performed intermediate, i.e. between patients and controls, on most measures, but were particularly characterised by reduced antisaccade gain. SPEM gain at one target velocity was significantly correlated between patients and siblings, highlighting the necessity of taking into account within-family correlations in the statistical analysis of between-group differences. It is concluded that subtle SPEM and antisaccade deficits are observed in clinically unaffected siblings of schizophrenia patients; these deficits may be useful markers of genetic liability to schizophrenia