Excellent Excitonic Photovoltaic Effect in 2D CsPbBr3/CdS Heterostructures. (11th September 2020)

• Record Type: Journal Article
• Authors: Jin, Bao; Zuo, Nian; Hu, Zhi‐Yi; Cui, Wenjun; Wang, Renyan; Van Tendeloo, Gustaaf; Zhou, Xing; Zhai, Tianyou
• Is Part Of: Advanced functional materials. Volume 30:Number 49(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-09-11
• Subjects: 2D materials -- CdS -- heterostructures -- perovskites -- photovoltaic device; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202006166
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: P–n photovoltaic junctions are essential building blocks for optoelectronic devices for energy conversion. However, this photovoltaic efficiency has almost reached its theoretical limit. Here, a brand‐new excitonic photovoltaic effect in 2D CsPbBr3 /CdS heterostructures is revealed. These heterostructures, synthesized by epitaxial growth, display a clean interface and a strong interlayer coupling. The excitonic photovoltaic effect is a function of both the built‐in equilibrium electrical potential energy and the chemical potential energy, which is generated by the significant concentration gradient of electrons and holes at the heterojunction interface. Excitingly, this novel photovoltaic effect results in a large open‐circuit voltage of 0.76 V and a high power conversion efficiency of 17.5%. In addition, high photodetection performance, including a high photoswitch ratio ( I light / I dark ) of 10 5 and a fast response rate of 23 µs are obtained. These findings provide a new platform for photovoltaic applications. Abstract : 2D CsPbBr3 /CdS flakes are achieved via epitaxial growth. The as‐synthesized heterostructures display high‐quality crystallization and strong interlayer coupling at the interface. Meanwhile, the device exhibits excellent excitonic photovoltaic effects, including large open‐circuit voltage (≈0.76 V), high power conversion efficiency (≈17.5%). In addition, a fast response time of 23 µs is achieved under zero bias for photodetection.