Layered Li9V3(P2O7)3(PO4)2 has attracted considerable interest as a novel cathode material for potential use in rechargeable lithium batteries. The defect chemistry, doping behavior and lithium diffusion paths in Li9V3(P2O7)3(PO4)2 are investigated using atomistic scale simulations. Here we show that the activation energy for Li migration via the vacancy mechanism is 0.72 eV along the c-axis. Additionally, the most favourable intrinsic defect type is Li Frenkel (0.44 eV/defect) ensuring the formation of Li vacancies that are required for Li diffusion via the vacancy mechanism. The only other intrinsic defect mechanism that is close in energy is the formation of anti-site defect, in which Li and V ions exchange their positions (1.02 eV/defect) and this can play a role at higher temperatures. Considering the solution of tetravalent dopants it is calculated that they require considerable solution energies, however, the solution of GeO2 will reduce the activation energy of migration to 0.66 eV.

The present study was carried out to analyse the inorganic and organic contents in the leaf ofDatura meteland to investigate the acute toxicity at varying concentrations on grasshoppers and red ants. We determined the calcium, magnesium and phosphorous in the ionic state quantitatively and carried out screening tests and solvent extraction using chloroform to find out the presence of organic groups such as alkaloids, flavanoids, saponins and steroids. The concentration of Ca2+, Mg2+, Fe3+and PO43-were found to be (4.28 ± 0.05)×104, (3.86 ± 0.009) ×104, (2.33 ± 0.007)×104and (4.65 ± 0.06)×104ppm respectively. The screening tests confirmed the presence of alkaloids and steroids and the absence of saponins and flavanoids. Increasing concentrations of the plant extracts (2500-15000 ppm) were added to grasshoppers (n = 10) and red ants (n = 10) in an experimental chamber. After 10 minutes of exposure, the numbers of live insects were counted. The results showed the EC50value was 12000 ppm for grasshoppers and 11600 ppm for red ants. Percentage mortality increased from 20-60% with increasing concentrations. Our results indicated that extract ofDatura metelleaves at higher concentrations was more toxic and it can be used as an insecticide against grasshoppers and red ants.

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In this study, force field-based simulations are employed to examine the defects in Li-ion diffusion pathways together with activation energies and a solution of dopants in Li2Ti6O13. The lowest defect energy process is found to be the Li Frenkel (0.66 eV/defect), inferring that this defect process is most likely to occur. This study further identifies that cation exchange (Li–Ti) disorder is the second lowest defect energy process. Long-range diffusion of Li-ion is observed in the bc-plane with activation energy of 0.25 eV, inferring that Li ions move fast in this material. The most promising trivalent dopant at the Ti site is Co3+, which would create more Li interstitials in the lattice required for high capacity. The favorable isovalent dopant is the Ge4+ at the Ti site, which may alter the mechanical property of this material. The electronic structures of the favorable dopants are analyzed using density functional theory (DFT) calculations.

There is growing interest to discover suitable calcium containing oxides that can be used as electrode materials in calcium ion batteries. A comprehensive computational investigation of ionic defects and Ca-ion diffusion in Ca-bearing oxide materials at the atomic level is important so as to predict their suitability for use in Ca-ion batteries. In this study, we apply atomistic simulation techniques to examine the energetics of defects, dopants, and Ca-ion diffusion in Ca3Fe2Si3O12. The calculations suggest that the Ca/Fe anti-site defect is the most favorable intrinsic defect causing such significant disorder, which would be sensitive to synthesis conditions. Diffusion of Ca2+ ions within Ca3Fe2Si3O12 is three-dimensional, with the activation energy of migration of 2.63 eV inferring slow ionic conductivity. The most favorable isovalent defects are Mn2+, Sc3+, and Ge4+ on Ca, Fe, and Si, respectively, for this process. The formation of extra calcium was considered to increase the capacity and diffusion of Ca in this material. It is found that Al3+ and Mn2+ are the candidate dopants on the Si and Fe sites, respectively, for this process and there is a reduction observed in the activation energies. The electronic structures of favorable dopant configurations are discussed using density functional theory simulations.