Enhancement of ion diffusion by targeted phonon excitation

被引：31

作者：

Gordiz, Kiarash ^{[1
]}

Muy, Sokseiha ^{[2
]}

Zeier, Wolfgang G. ^{[3
]}

Shao-Horn, Yang ^{[1
,2
,4
]}

Henry, Asegun ^{[1
]}

机构：

[1] MIT, Dept Mech Engn, Cambridge, MA 02139 USA

[2] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA

[3] Univ Munster, Inst Inorgan & Analyt Chem, Corrensstr 30, D-48149 Munster, Germany

[4] MIT, Res Lab Elect, 77 Massachusetts Ave, Cambridge, MA 02139 USA

来源：

CELL REPORTS PHYSICAL SCIENCE | 2021年 / 2卷 / 05期

基金：

美国国家科学基金会;

关键词：

SOLID-STATE ELECTROLYTES; LATTICE-DYNAMICS; SUPERIONIC TRANSITION; MECHANISTIC INSIGHTS; LITHIUM; TRANSPORT; CONDUCTIVITY; SIMULATIONS; RELAXATION; PRINCIPLES;

D O I：

10.1016/j.xcrp.2021.100431

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Ion diffusion is important in a variety of applications, yet fundamental understanding of the interaction of phonons and the mobile species in solids is still missing. In this work, we introduce two for malisms that determine the individual contributions of phonons to the diffusion of ions through a solid, based on nudged elastic-band calculations and molecular dynamics simulations. The results for a model ion conductor of Ge-substituted Li3PO4 (Li3.042-Ge0.042P0.958O4) reveal that more than 87% of the Li+ ion diffusion originates from less than 10% of the vibrational modes between 8 and 20 THz. By deliberately exciting a small, targeted subset of these contributing modes (<1%) to a higher temperature and still keeping the lattice at a low temperature, we observe an increase in diffusivity by several orders of magnitude. This new understanding identifies new avenues for increasing diffusivity by engineering the vibrations in a material without necessarily changing the compound chemistry.

引用

页数：18

共 98 条

[1] Diffusons, locons and propagons: character of atomic vibrations in amorphous Si [J].