Understanding and Designing Novel H- Ionic Conductors Based on First Principles Calculations

Tuesday, 3 October 2017: 10:40
National Harbor 4 (Gaylord National Resort and Convention Center)
Q. Bai and Y. Mo (University of Maryland, College Park)
In contrast to proton (H+) conductor materials, hydride ion (H-) conductors are exceedingly rare in nature. Hydride ions are attractive charge carriers with a strong reducing property comparable to that of Mg, indicating potential high voltage and high energy densities. Recently, pure H- conduction in new La2-x-ySrx+yLiH1-x+yO3-y oxyhydrides has been demonstrated in experiments, opening a promising avenue for exploring new battery chemistry based on hydride ions. In this presentation, we will elucidate the H- diffusion mechanism in the distinctive structures of these new oxyhydrides, using first principles calculations. On the basis of our newly gained understandings of H- diffusion, we performed first principles computation to further optimize and design the oxyhydrides with enhanced properties. Our study demonstrated first principles computation approach for in-depth understanding of new materials and accelerated materials designing with enhanced properties, and is highly transferable to other materials.