Is Defect Segregation Facile in the Grain Boundary of Methylammonium Lead Iodide?

POSTER

Abstract

Methylammonium Lead Iodide (MAPbI3) is emerging as one of the most promising materials for solar cells. Grain boundaries (GBs) and native point defects are ubiquitous in MAPbI3 given that solution-based methods generate polycrystalline materials. Our previous study has shown that there is a strong thermodynamic preference of iodine point defects to exist in the GB region rather than in the interior of the MAPbI3 grain [Shan and Saidi, J. phys. Chem Lett. 8, 5935 (2017)]. This would generate defect segregation to the GB, provided that defect diffusion is not hindered at room temperature. In this talk, we examine the energy barriers and possible kinetic limitations of the diffusion of iodine interstitials and vacancies in Σ5 (210) MAPbI3 GB, and contrast the results with their diffusion in crystalline system.

Presenters

  • Xin He

    Jilin University, School of Materials Science and Engineering, Jilin University, Jinlin University

Authors

  • Xin He

    Jilin University, School of Materials Science and Engineering, Jilin University, Jinlin University

  • Wissam Saidi

    Mechanical Engineering and Materials Science, University of Pittsburgh, University of Pittsburgh, Mechanical Engineering & Materials Science, University of Pittsburgh

  • Lijun Zhang

    Jilin University, School of Materials Science and Engineering, Jilin University, College of Materials Science and Engineering, Jilin University, Jinlin University