Abstract
Halide perovskites have undergone remarkable developments as highly efficient optoelectronic materials for a variety of applications. Several studies indicated the critical role of defects on the performance of perovskite devices. However, the parameters of defects and their interplay with free charge carriers remain unclear. In this study, we explored the dynamics of free holes in methylammonium lead tribromide (MAPbBr3) single crystals using the time-of-flight (ToF) current spectroscopy. By combining ToF spectroscopy and Monte Carlo simulation, three energy states were detected in the bandgap of MAPbBr3. In addition, we found the trapping and detrapping rates of free holes ranging from a few microseconds to hundreds of microseconds. Contrary to previous studies, we revealed a strong detrapping activity of traps. We showed that these traps substantially affect the transport properties of MAPbBr3, including mobility and mobility-lifetime product. Our results provide an insight on charge transport properties of perovskite semiconductors.
| Original language | English |
|---|---|
| Article number | eabb6396 |
| Journal | Science Advances |
| Volume | 6 |
| Issue number | 37 |
| DOIs | |
| State | Published - Sep 2020 |
| Externally published | Yes |
Funding
A.M., J.P., P.P., M.B., E.B., and R.G., thank the Institute of Physics of Charles University for providing necessary facilities to conduct this research. Funding: A.M., J.P., P.P., M.B., E.B., and R.G acknowledge financial support from the Grant Agency of the Czech Republic, grant no. P102/19/11920S, and the Grant Agency of Charles University, project no. 1234119. M.A. and B.D. acknowledge financial support from U.S. Department of Homeland Security (grant no. 16DNARI00018-04-0). M.-H.D. is supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences, and Engineering Division. Author contributions: A.M. and M.A. wrote the paper. A.M. conceived the idea and conducted the experiments. M.A. and B.D. grew the perovskite single crystals and performed the device fabrication. P.P., E.B., and A.M. contributed to the design of the experimental setup. J.P. and A.M. performed the theoretical calculations. A.M. and R.G. supervised the theoretical simulation. M.-H.D. contributed to the defect nature assignment. M.B., J.P., and A.M. contributed to the figures and preparation of video materials. All authors contributed to results’ discussion and approved the final version. Competing interests: The authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in this paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the corresponding author, A.M.