Issue 35, 2021

Understanding the interfacial charge transfer in the CVD grown Bi2O2Se/CsPbBr3 nanocrystal heterostructure and its exploitation in superior photodetection: experiment vs. theory

Abstract

Efficient charge transfer in a 2D semiconductor heterostructure plays a crucial role in high-performance photodetectors and energy harvesting devices. Non-van der Waals 2D Bi2O2Se has enormous potential for high-performance optoelectronics, though very little is known about the interfacial charge transport at the corresponding 2D heterojunction. Herein, we report a combined experimental and theoretical investigation of interfacial charge transfer in the Bi2O2Se/CsPbBr3 heterostructure through various microscopic and spectroscopic tools corroborated with density functional theory calculations. The CVD-grown few-layer Bi2O2Se nanosheet possesses high crystallinity and a high absorption coefficient in the visible-near IR region. We integrated the few-layer Bi2O2Se nanosheet possessing superior electron mobility and CsPbBr3 nanocrystals with high light-harvesting capability for efficient broadband photodetection. The band alignment reveals a type-I heterojunction, and the device under reverse bias reveals a fast response time of 12 μs/24 μs (rise time/fall time) and an improved responsivity in the 390 to 840 nm range due to the effective interfacial charge transfer and efficient interlayer coupling at the Bi2O2Se/CsPbBr3 interface. Notably, a photodetector with a better light on/off ratio and a peak responsivity of ∼103 A W−1 was achieved in the Bi2O2Se/CsPbBr3 heterostructure due to the synergistic effects in the heterostructure under ambient conditions. The DFT analysis of the density of states and charge density plots in the heterostructure revealed a net transfer of electrons/holes from perovskite nanocrystals to Bi2O2Se layers and additional density of states in Bi2O2Se. These results are significant for the development of non-van der Waals heterostructure based high-performance low-powered photodetectors.

Graphical abstract: Understanding the interfacial charge transfer in the CVD grown Bi2O2Se/CsPbBr3 nanocrystal heterostructure and its exploitation in superior photodetection: experiment vs. theory

Supplementary files

Article information

Article type
Paper
Submitted
09 Jul 2021
Accepted
12 Aga 2021
First published
13 Aga 2021

Nanoscale, 2021,13, 14945-14959

Understanding the interfacial charge transfer in the CVD grown Bi2O2Se/CsPbBr3 nanocrystal heterostructure and its exploitation in superior photodetection: experiment vs. theory

M. T. Hossain, M. Das, J. Ghosh, S. Ghosh and P. K. Giri, Nanoscale, 2021, 13, 14945 DOI: 10.1039/D1NR04470B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements