Individual Electron and Hole Mobilities in Lead-Halide Perovskites Revealed by Noncontact Methods

Matthew Beard, Yaxin Zhai, Kang Wang, Fei Zhang, Chuanxiao Xiao, Aaron Rose, Kai Zhu

Research output: Contribution to journalArticlepeer-review

39 Scopus Citations

Abstract

Charge carrier mobilities help determine semiconductor performance in optoelectronic applications, but measurement of the individual electron and hole mobilities usually involves indirect methods or probes with electrical contacts that are influenced by the quality of the interface or contact. Here, a noncontact method is introduced to distinguish the mobilities of electrons and holes by combining time-resolved terahertz spectroscopy (TRTS) and optical transient reflection (TR) spectroscopy. The validation of this method is first demonstrated on a semi-insulator GaAs wafer, and then, three lead-halide perovskite polycrystalline films with different cation mixtures are studied. We find that the hole mobility is significantly higher (∼10×) than that of the electron mobility in all of the perovskite thin films studied. The highly alloyed triple cation polycrystalline film shows the highest mobility, longest bulk carrier lifetime, and lowest surface recombination velocity.

Original languageAmerican English
Pages (from-to)47-55
Number of pages9
JournalACS Energy Letters
Volume5
Issue number1
DOIs
StatePublished - 10 Jan 2020

Bibliographical note

Publisher Copyright:
© 2019 American Chemical Society.

NREL Publication Number

  • NREL/JA-5900-74898

Keywords

  • carrier mobility
  • perovskite thin films
  • THz

Fingerprint

Dive into the research topics of 'Individual Electron and Hole Mobilities in Lead-Halide Perovskites Revealed by Noncontact Methods'. Together they form a unique fingerprint.

Cite this