Abstract
One of the current challenges in methylammonium lead halide (MAPbX3) perovskite application research is understanding contact formation and interfacial phenomena for highly efficient and stable device performance. For semiconductors, development of contact formation is inseparable from device performance and stability. Single-crystalline MAPbX3 has become of great interest for perovskite devices in photodetectors, light-emitting diodes, and more recently in high-energy radiation detection. Deeper research is required to understand interfacial interactions in single-crystalline MAPbX3. This article focuses on the dynamic impact of electrode metal (Au and Cr) on methylammonium lead bromide (MAPbBr3) single crystals. It is studied how charge transport properties of single crystal MAPbBr3 can be tuned via electrode material selection at the metal/MAPbBr3 interface to improve device performance with proper contact formation. The ability to create an ohmic-like or nonohmic contact by switching the electrode metal from Cr to Au, respectively, is demonstrated. It is observed that the interfacial charge transfer resistance (recombination resistance) of the Cr/MAPbBr3 interface is 1.79 × 109 Ω, compared to 1.32 × 107 Ω for the Au/MAPbBr3. Cr contacts can reduce hysteretic behavior by reducing interfacial recombination and interfacial polarization. These studies provide insight to metal/MAPbX3 interfacial interactions toward device engineering for hole transport layer-free MAPbX3 device structures.
| Original language | English |
|---|---|
| Article number | 1800476 |
| Journal | Advanced Materials Interfaces |
| Volume | 5 |
| Issue number | 18 |
| DOIs | |
| State | Published - Sep 21 2018 |
Funding
The authors thank the Center for Materials Processing (J.T.T.), a Center of Excellence at the University of Tennessee, Knoxville funded by the Tennessee Higher Education Commission (THEC), for financial support. Part of this research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility at Oak Ridge National Laboratory. XRD was performed at the Joint Institute for Advanced Materials (JIAM) Diffraction Facility, located at the University of Tennessee, Knoxville. This research was financially supported by the Domestic Nuclear Detection Office of the Department of Homeland Security (2016-DN-077-ARI01). Disclaimer: The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Department of Homeland Security.
Keywords
- hysteresis
- impedance spectroscopy
- interfaces
- ion migration
- metal electrodes
- methylammonium lead halide perovskites
