Organic Cation Engineering for Vertical Charge Transport in Lead‐Free Perovskite Quantum Wells
Abstract
2D organic–inorganic hybrid halide perovskites are promising semiconductor materials for a variety of device applications. However, fundamental issues of charge transport through multiple quantum wells separated by bulky organic ligands remain unsolved. Herein, a mixture of π‐conjugated organic ligands, (2‐(3‴,4′‐dimethyl‐[2,2′:5′,2′:5″,2‴‐quaterthiophen]‐5‐yl)ethan‐1‐ammonium iodide) (4Tm) and 2‐([2,2′‐bithiophen]‐5‐yl)ethan‐1‐aminium iodide (2T), is used as spacer to form (4Tm)x(2T)2−xSnI4 2D perovskite thin films. The new strategy of alloying 2T into 4Tm ligands reduces the interlayer distance (barrier thickness) while maintaining the relatively small energy barrier height for the hybrid quantum wells, enhances interlayer interactions, and improves charge transport across adjacent perovskite layers. Moreover, solar cell devices fabricated with (4Tm)x(2T)2−xSnI4 exhibit improved photovoltaic properties and stability.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 07, 2021
- Source ID
- 10.1002/smsc.202000024
Entities
People
- Blake P Finkenauer
- Bryan W Boudouris
- Jianguo Mei
- Ke Ma
- Letian Dou
- Libai Huang
- Linrui Jin
- Sheng-ning Hsu
- Yao Gao
- Zitang Wei
Organizations
- National Science Foundation
- Office of Naval Research
- Purdue University