TY - JOUR
T1 - Dual-sized carbon quantum dots enabling outstanding silicon-based photodetectors
AU - Hsiao, Po Hsuan
AU - Lai, Yen Chuan
AU - Chen, Chia Yun
N1 - Funding Information:
This work was supported by Ministry of Science and Technology of Taiwan (MOST 107-2221-E-006-013-MY3), and Hierarchical Green-Energy Materials (Hi-GEM) Research Center, from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) and the Ministry of Science and Technology (MOST 107-3017-F-006 -003) in Taiwan. The authors greatly thank the Instrument Center and Center for Micro/Nano Science and Technology, National Cheng Kung University with the facilities provided for conducting material characterizations.
Funding Information:
This work was supported by Ministry of Science and Technology of Taiwan (MOST 107-2221-E-006-013-MY3), and Hierarchical Green-Energy Materials (Hi-GEM) Research Center, from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) and the Ministry of Science and Technology (MOST 107-3017-F-006 -003) in Taiwan. The authors greatly thank the Instrument Center and Center for Micro/Nano Science and Technology, National Cheng Kung University with the facilities provided for conducting material characterizations.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/3/15
Y1 - 2021/3/15
N2 - Broadband and reliable photodetectors were in high demand due to their potential applications for optical communications, sensing and photoelectronic switches. Here, the facile in-situ formation of dual-sized carbon quantum dot (CQD) films featuring dense contact with silicon (Si) substrates that avoided the formation of interface oxide was demonstrated. The unique features of dual-size graded CQDs constituted the bottom layer of 10-nm CQDs functioning as the main light harvester and facilitating the heterojunction establishment with Si, while the top component of 6-nm CQDs at top featuring the electron blocking layer as well as hole extractor. Such heterostructures allowed the low dark current which was an order of magnitude less than monodispersed CQDs, and manifested the sound operation stability under systematic examinations including abrasion test, variations of temperature and environmental pH conditions and long-term switching test. In addition, the dependence of photocurrent on light intensity was fitted with power law relationship, showing the fairly identical characteristics by examining light illuminations of 850 nm, 580 nm, and 352 nm, respectively, which validated the wavelength-independent and compelling photodetection quality. These results represented a significant advancement in photodetector design with all-solution synthesis and pronounced high performances.
AB - Broadband and reliable photodetectors were in high demand due to their potential applications for optical communications, sensing and photoelectronic switches. Here, the facile in-situ formation of dual-sized carbon quantum dot (CQD) films featuring dense contact with silicon (Si) substrates that avoided the formation of interface oxide was demonstrated. The unique features of dual-size graded CQDs constituted the bottom layer of 10-nm CQDs functioning as the main light harvester and facilitating the heterojunction establishment with Si, while the top component of 6-nm CQDs at top featuring the electron blocking layer as well as hole extractor. Such heterostructures allowed the low dark current which was an order of magnitude less than monodispersed CQDs, and manifested the sound operation stability under systematic examinations including abrasion test, variations of temperature and environmental pH conditions and long-term switching test. In addition, the dependence of photocurrent on light intensity was fitted with power law relationship, showing the fairly identical characteristics by examining light illuminations of 850 nm, 580 nm, and 352 nm, respectively, which validated the wavelength-independent and compelling photodetection quality. These results represented a significant advancement in photodetector design with all-solution synthesis and pronounced high performances.
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U2 - 10.1016/j.apsusc.2020.148705
DO - 10.1016/j.apsusc.2020.148705
M3 - Article
AN - SCOPUS:85097587294
SN - 0169-4332
VL - 542
JO - Applied Surface Science
JF - Applied Surface Science
M1 - 148705
ER -