Qualifying composition dependent p and n self-doping in CH₃NH₃PbI₃

Authors

Qi Wang, University of Nebraska-Lincoln
Yuchuan Shao, University of Nebraska-Lincoln
Haipeng Xie, Central South University
Lu Lyu, Central South University
Xiaoliang Liu, Central South University
Yongli Gao, University of Rochester
Jinsong Huang, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2014

Citation

APPLIED PHYSICS LETTERS 105, 163508 (2014)

Comments

Copyright 2014 AIP Publishing LLC

Abstract

We report the observation of self-doping in perovskite. CH₃NH₃PbI₃ was found to be either n- or p-doped by changing the ratio of methylammonium halide (MAI) and lead iodine (PbI₂) which are the two precursors for perovskite formation. MAI-rich and PbI₂-rich perovskite films are p and n self-doped, respectively. Thermal annealing can convert the p-type perovskite to n-type by removing MAI. The carrier concentration varied as much as six orders of magnitude. A clear correlation between doping level and device performance was also observed.