Using Bulk Heterojunctions and Selective Electron Trapping to Enhance the Responsivity of Perovskite–Graphene Photodetectors
Abstract
Graphene field effect transistor sensitized by a layer of semiconductor (sensitizer/GFET) is a device structure that is investigated extensively for ultrasensitive photodetection. Among others, organometallic perovskite semiconductor sensitizer has the advantages of long carrier lifetime and solution processable. A further step to improve the responsivity is to design a structure that can promote electron–hole separation and selective carrier trapping in the sensitizer. Here, the use of a hybrid perovskite–organic bulk heterojunction (BHJ) as the light sensitizer to achieve this goal is demonstrated. Our spectroscopy and device measurements show that the CH3NH3PbI3–PCBM BHJ/GFET device has improved charge separation yield and carrier lifetime as compared to a reference device with a CH3NH3PbI3 sensitizer only. The key to these enhancement is the presence of [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM), which acts as charge separation and electron trapping sites, resulting in a 30‐fold increase in the photoresponsivity. This work shows that the use of a small amount of electron or hole acceptors in the sensitizer layer can be an effective strategy for improving and tuning the photoresponsivity of sensitizer/GFET photodetectors.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 23, 2017
- Source ID
- 10.1002/adfm.201704173
Entities
People
- Bhupal Kattel
- Chunhai Li
- Judy Z. Wu
- Liang Qin
- Liping Wu
- Wai-Lun Chan
- Yanbing Hou
- Yong Zhang
Organizations
- Army Research Office
- Beijing Jiaotong University
- Division of Materials Research
- National Natural Science Foundation of China
- Shanghai Jiao Tong University
- University of Kansas
- Xi'an Jiaotong University