Active Li‐ion battery materials are typically characterized using X‐ray photoelectron spectroscopy when regarding chemical state elucidation. This work presents a multiplet‐splitting approach ...comprising in minimum 3 third‐row transition metals, namely, Mn, Co, and Ni, to improve the results in comparison to peak barycenter or single symmetric Voigt profile approaches. The achieved X‐ray photoelectron spectroscopy 2p templates in particular address the complex peak structures consisting of significant photoelectron multiplet splitting, shake‐up and plasmon loss features, and additional Auger and photoelectron overlaps, inevitable also for a reliable quantification. To separate from topography effects and contributions of the electrode's binder and conductive carbon in powder electrodes, the developed procedure in a first attempt was successfully transferred to novel radio frequency magnetron sputtered Li‐Ni‐Co‐Mn‐O thin films, designed for all‐solid‐state Li‐ion batteries. In all cases, special care was taken with respect to air sensitivity, contamination during sample handling, and probable method induced sample decomposition.
To improve the electrochemical properties of Li(Ni1/3Mn1/3Co1/3)O2 (NMC) like Lithium-diffusion rate or rate capability one way is to increase the surface between the cathode and electrolyte. By ...sputter etching of stainless steel substrates the surface topography is varied. Lithium-rich Li-Ni-Mn-Co-O thin film cathodes are deposited onto these modified stainless steel substrates by non-reactive r.f. magnetron sputtering from a ceramic Li1.14(Ni0.37Mn0.18Co0.32)O1.19 target. Microstructure and electrical properties were characterized by X-ray diffraction (GIXRD), Raman spectroscopy, Atomic-force microscopy (AFM) and impedance spectroscopy (IS). The substrate roughness was increased from Ra = 4 nm to Ra = 63 nm after 180 min of sputter etching. The crystal orientation wasn’t influenced significant by the pre deposition surface topography modification. The results show that the activation energy EA of the conductivity mechanism is 0.23 eV, independent of the pre-deposition sputter etching treatment. Also the pre-deposition sputter etching increases the conductivity from 1.49·10−11 Scm−1 to 1.75·10−10 Scm−1 at 20 °C. Correlations between process parameters, microstructure and electrical behaviour are discussed in detail.
•The substrate roughness was increased and adjusted by a pre-deposition etching process.•Lithium rich Li-Ni-Mn-Co-O films have been deposited on substrates with different surface topography.•The activation energy of the conduction mechanism was determined for Li-Ni-Mn-Co-O films.•The Microstructure and the activation energy is independent of the surface roughness.•The conductivity increases with increased and adjusted roughness.
GaN films with thickness up to 3 mm were grown by halide vapour phase epitaxy method. Two growth modes were observed: the high temperature (HT) mode and the low temperature (LT) mode. Films grown in ...HT mode had smooth surface, however the growth stress was high and caused cracking. Films grown in LT mode had rough surface with high density of V-defects (pits), however such films were crack-free. The influence of growth parameters on the pit shape and evolution was investigated. Origins of pits formation and process of pit overgrowth are discussed. Crack-free films with smooth surface and reduced density of pits were grown using combination of the LT and HT growth modes.
Molecular dynamics simulations based on density functional theory have been systematically performed to study amorphous Si37.5Al51.7M10.8 anodes (M=3d metals) for Li ion batteries. All anode ...materials studied possess a factor of ~10 larger volumetric capacities than graphite. Furthermore, they exhibit an order of magnitude reduced volume expansion upon Li incorporation (in the order of 1%) compared to graphite (12%). The V-containing anode is found to show the highest Li mobility. The high Li mobility may be explained by a fivefold weaker interaction between Li and the matrix elements compared to graphite. Si35.4Al55.9V8.7 and Si35.2Al55.5Co9.3 amorphous thin film anodes were synthesized by magnetron sputtering and their volumetric capacities were measured. In spite of a large capacity drop after the first cycle, their initial discharge volumetric capacities are superior to graphite and comparable to those of pure Si with equivalent thickness.
•Amorphous Si–Al–V is found to be promising anode for LIBs based on quantum design.•The first volumetric capacity of amorphous Si–Al–V anode is superior to graphite.•A quantum mechanical route to design anodes is proposed.
Aims
This report presents the clinical course, neuropathology and ultrastructure of neuronal tau inclusions of four Slovene relatives with P364S MAPT mutation.
Methods
The clinical history of three ...out of four P364S MAPT mutation carriers was taken. After formalin fixation, thorough sampling of the central nervous system was followed by paraffin embedding, H&E, Gallyas, Bielschowsky and immunostaining with AT8, anti‐3R, anti‐4R tau, anti‐amyloid‐β, anti‐TDP43 and anti‐alpha‐synuclein antibodies. The distribution and density of different types of neuronal tau inclusions were semiquantitatively assessed. In addition, the ultrastructure of neuronal tau inclusions was analysed.
Results
Macroscopic examination of the brains was unremarkable. Microscopically, neuronal tau inclusions of almost all known types were widespread and distributed fairly uniformly in all cases. Pick bodies and swollen neurones were found in only one family member. Mutant tau was composed of 3R and 4R isoforms, with a slight predominance of 3R tau. Composite neuronal tau inclusion (CNTI), found in all four relatives, was a hallmark of the P364S MAPT mutation. CNTI showed compartmental differences in H&E and Gallyas staining, tau isoforms immunolabelling and ultrastructure, displaying fuzzy fibrils in the core and paired twisted tubules at the periphery.
Conclusions
P364S MAPT mutation is characterized clinically by a variable combination of frontotemporal dementia, parkinsonism and motor neurone disease of short duration, and neuropathologically by a widespread uniform distribution of all known neuronal tau inclusions in one family member. Two‐compartment CNTI is a unique characteristic of the P364S MAPT mutation.
PDF
