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Title: A comparative study of broadband PbS quantum dots/graphene photodetectors with monolayer and bilayer graphene
Abstract Colloidal quantum dots (QDs)/graphene nanohybrids provide a unique platform to design photodetectors of high performance. These photodetectors are quantum sensors due to the strong quantum confinement in QDs for spectral tunability, and in graphene for high charge mobility. Quantitatively, the high carrier mobility of graphene plays a critical role to enable high photoconductive gain and understanding its impact on the photodetector performance is imperative. Herein, we report a comparative study of PbS QDs/graphene nanohybrids with monolayer and bilayer graphene for broadband photodetection ranging from ultraviolet, visible, near-infrared to short-wave infrared spectra (wavelength: 400 nm–1750 nm) to determine if a specific advantage exists for one over the other. This study has revealed that both the monolayer and bilayer graphene grown in chemical vapor deposition can provide a highly efficient charge transfer channel for photo-generated carriers for high broadband photoresponse.  more » « less
Award ID(s):
2149897 2314401 2322053
PAR ID:
10541133
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Nano Express
Volume:
5
Issue:
3
ISSN:
2632-959X
Format(s):
Medium: X Size: Article No. 035019
Size(s):
Article No. 035019
Sponsoring Org:
National Science Foundation
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