Human Factor Ba

LaTiO2N has been considered as one of the most promising photocatalysts for solar energy conversion. Nevertheless, it generally has a poor photocatalytic activity under normal conditions, probably linked to severe structural distortions and various types of defects within this compound. Herein, we modified LaTiO2N by introducing Ba into its A sit; that is, La0.8Ba0.2Ti0 2.2N0.8. The presence of Ba at the A site of LaTiO2N not only relaxes the structural distortions but also effectively inhibits defect formation (e.g. Ti3+ species) in LaTiO2N. Moreover, surface hydrophilicity of LaTiO2N is also improved by Ba modification. Photoelectrochemical analysis suggests that charge separation and transferring situation are ameliorated in Ba-modified LaTiO2N, and the valence band edge position is positively shifted. These factors are likely the reasons for the improved photocatalytic activity of La(0.8)Ba(0.2)Ti(0 2.2)N(0.8 )in water oxidation reactions.

The derivatives of LiTi2(PO4)(3) are promising electrolytes for solid-state batteries. An extensive molecular dynamics study is performed employing a refined set of potential parameters to understand the influence of Ba substitution on Li+ ion conductivity in Bax/2Li1-xTi2(PO4)(3) (0.0 <= x <= 0.83). The refined set of potential parameters reveals the structural and dynamical properties of Bax/2Li1-xTi2(PO4)(3) which are consistent with experimental results. In the presence of Ba2+, the system endures a persistent competition between the generation of vacant Li-sites and blocking of Li+ ion paths. The diffusivity of Li+ ions enhances with x and increases one order of magnitude higher at x = 0.67, where the creation of vacant Li-sites mainly drives the diffusion. This trend is similar to the experimental report. However, for x 4 0.67 compositions, the blocking of the Li+ ion path dominates in the presence of immobile Ba2+ ions, resulting in a reduction of Li+ ion diffusion. The present study also proposes an ordered substitution of Ba2+ ions at crystallographically identified Li1-sites, where an extra Li-site generation is identified at higher compositions. In this case, the vacancy strongly dominates over Li+ ion path blocking, resulting in the possibility to achieve even higher Li+ ion diffusion. The creation of extra Li-sites and mechanism of Li+-ion transport are studied systematically with varying compositions. Further insight into Li+ ion transport is gained by constructing a three-dimensional density map and determining the free energy barrier and clustering of Li+ ion probability density. And the factors affecting the cation diffusion are also systematically investigated.