Fluid-enhanced surface diffusion controls intraparticle phase transformations.

Autor: Li Y; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.; Sandia National Laboratories, Livermore, CA, USA., Chen H; Department of Chemistry, University of Bath, Bath, UK., Lim K; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA.; Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Deng HD; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA., Lim J; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Fraggedakis D; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA., Attia PM; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA., Lee SC; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA., Jin N; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA., Moškon J; National Institute of Chemistry, Ljubljana, Slovenia., Guan Z; Department of Applied Physics, Stanford University, Stanford, CA, USA., Gent WE; Department of Chemistry, Stanford University, Stanford, CA, USA., Hong J; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA.; Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA., Yu YS; Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA., Gaberšček M; National Institute of Chemistry, Ljubljana, Slovenia.; Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia., Islam MS; Department of Chemistry, University of Bath, Bath, UK. m.s.islam@bath.ac.uk., Bazant MZ; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA. bazant@mit.edu.; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA. bazant@mit.edu.; Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA. bazant@mit.edu.; SUNCAT Interfacial Science and Catalysis, Stanford University, Stanford, CA, USA. bazant@mit.edu., Chueh WC; Department of Materials Science & Engineering, Stanford University, Stanford, CA, USA. wchueh@stanford.edu.; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. wchueh@stanford.edu.
Jazyk: angličtina
Zdroj: Nature materials [Nat Mater] 2018 Oct; Vol. 17 (10), pp. 915-922. Date of Electronic Publication: 2018 Sep 17.
DOI: 10.1038/s41563-018-0168-4
Abstrakt: Phase transformations driven by compositional change require mass flux across a phase boundary. In some anisotropic solids, however, the phase boundary moves along a non-conductive crystallographic direction. One such material is Li X FePO 4 , an electrode for lithium-ion batteries. With poor bulk ionic transport along the direction of phase separation, it is unclear how lithium migrates during phase transformations. Here, we show that lithium migrates along the solid/liquid interface without leaving the particle, whereby charge carriers do not cross the double layer. X-ray diffraction and microscopy experiments as well as ab initio molecular dynamics simulations show that organic solvent and water molecules promote this surface ion diffusion, effectively rendering Li X FePO 4 a three-dimensional lithium-ion conductor. Phase-field simulations capture the effects of surface diffusion on phase transformation. Lowering surface diffusivity is crucial towards supressing phase separation. This work establishes fluid-enhanced surface diffusion as a key dial for tuning phase transformation in anisotropic solids.
Databáze: MEDLINE
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