Li3V2(PO4)3 Cathode Material: Synthesis Method, High Lithium Diffusion Coefficient and Magnetic Inhomogeneity.

Li3V2(PO4)3 cathodes for Li-ion batteries (LIBs) were synthesized using a hydrothermal method with the subsequent annealing in an argon atmosphere to achieve optimal properties. The X-ray diffraction analysis confirmed the material's single-phase nature, while the scanning electron microscopy revealed a granular structure, indicating a uniform particle size distribution, beneficial for electrochemical performance. Magnetometry and electron spin resonance studies were conducted to investigate the magnetic properties, confirming the presence of the relatively low concentration and highly uniform distribution of tetravalent vanadium ions (V4+), which indicated low lithium deficiency values in the original structure and a high degree of magnetic homogeneity in the sample, an essential factor for consistent electrochemical behavior. For this pure phase Li3V2(PO4)3 sample, devoid of any impurities such as carbon or salts, extensive electrochemical property testing was performed. These tests resulted in the experimental discovery of a remarkably high lithium diffusion coefficient D = 1.07 × 10-10 cm2/s, indicating excellent ionic conductivity, and demonstrated impressive stability of the material with sustained performance over 1000 charge-discharge cycles. Additionally, relithiated Li3V2(PO4)3 (after multiple electrochemical cycling) samples were investigated using scanning electron microscopy, magnetometry and electron spin resonance methods to determine the extent of degradation. The combination of high lithium diffusion coefficients, a low degradation rate and remarkable cycling stability positions this Li3V2(PO4)3 material as a promising candidate for advanced energy storage applications.

Vascular plant occurrences in grasslands of Central Forest Nature Reserve (Russia): a dataset.

BACKGROUND: Here we present the sampling event dataset that contributes to studying the flora of grasslands in Central Forest State Nature Biosphere Reserve (part of the UNESCO World Network of Biosphere Reserves), Tver Oblast, Russia. The Reserve is located in the SW part of the Valdai Upland within the main Caspian-Baltic watershed of the Russian plain (Latitude: 56° 26' - 56° 39' N, Longitude: 32° 29' - 33° 01' E). The territory of Central Forest Reserve belongs to the subzone of subtaiga. NEW INFORMATION: The dataset includes the occurrences of vascular plant species in four types of grasslands from 209 vegetation plots (8,506 associated occurrences), collected in 2013-2014. The dataset described in this paper has never been published before.As the grasslands in Central Forest State Nature Biosphere Reserve are relatively unstudied, we are providing a new comprehensive dataset on the vascular plant species occurrences in the grasslands of the Reserve. The dataset contains representative information on floristic composition of plant communities in localities with assigned GPS coordinates. As the vegetation of the Reserve is typical of the subtaiga subzone, the results of analysing this dataset can be useful for grassland management in the whole subtaiga subzone.During this study, we found one vascular plant species included in the Red Data Book of the Russian Federation, three species from the Red Data Book of Tver Oblast, as well as 10 alien vascular plant species for the Reserve. These data, especially, the occurrences of protected and alien species, contribute to our knowledge of species composition of the grasslands of the Reserve.

Synthesis, Structural, Thermal, and Electronic Properties of Palmierite-Related Double Molybdate α-Cs2Pb(MoO4)2.

Cs2Pb(MoO4)2 crystals were prepared by crystallization from their own melt, and the crystal structure has been studied in detail. At 296 K, the molybdate crystallizes in the low-temperature α-form and has a monoclinic palmierite-related superstructure (space group C2/m, a = 2.13755(13) nm, b = 1.23123(8) nm, c = 1.68024(10) nm, ß = 115.037(2)°, Z = 16) possessing the largest unit cell volume, 4.0066(4) nm3, among lead-containing palmierites. The compound undergoes a distortive phase transition at 635 K and incongruently melts at 943 K. The electronic structure of α-Cs2Pb(MoO4)2 was explored by using X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy methods. For α-Cs2Pb(MoO4)2, the photoelectron core-level and valence-band spectra and the XES band representing the energy distribution of Mo 4d and O 2p states were recorded. Our results allow one to conclude that the Mo 4d and O 2p states contribute mainly to the central part and at the top of the valence band, respectively, with also significant contributions throughout the whole valence-band region of the molybdate under consideration.