2018/10/31 by A. Chatzichristos, Aris Chatzichristos, R. M. L. McFadden +20 · 5 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Activation energy #Advanced Battery Materials and Technologies #Advancements in Battery Materials #Analytical Chemistry (journal) #Arrhenius equation #Chemistry #Diffusion #Electron and X-Ray Spectroscopy Techniques #Geometry #Materials science #Physical chemistry #Physics #Rutile #Surface (topology) #Thermal diffusivity #Thermodynamics #Trapping #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevlett.123.095901
published in Physical Review Letters 123(9), 095901 (American Physical Society) · 5 pages, 4 figures
openalex created_date 2018/11/09 · arxiv created 2019/03/01 · openalex publication_date 2019/08/29 · arxiv updated 2019/09/02 · openalex updated_date 2026/08/06
We report measurements of the diffusion rate of isolated ion-implanted 8Li+ within ∼120 nm of the surface of oriented single-crystal rutile TiO2 using a radiotracer technique. The α particles from the 8Li decay provide a sensitive monitor of the distance from the surface and how the depth profile of 8Li evolves with time. The main findings are that the implanted Li+ diffuses and traps at the (001) surface. The T dependence of the diffusivity is described by a bi-Arrhenius expression with activation energies of 0.3341(21) eV above 200 K, whereas at lower temperatures it has a much smaller barrier of 0.0313(15) eV. We consider possible origins for the surface trapping, as well the nature of the low-T barrier.