Identifying Carrier Behavior in Ultrathin Indirect-Bandgap CsPbX3 Nanocrystal Films for Use in UV/Visible-Blind High-Energy Detectors
Type
ArticleAuthors
Xin, Bin
Alaal, Naresh
Mitra, Somak

Subahi, Ahmad
Pak, Yusin
Almalawi, Dhaifallah
Alwadai, Norah M.

Lopatin, Sergei
Roqan, Iman S.

KAUST Department
Electron MicroscopyMaterial Science and Engineering Program
Physical Science and Engineering (PSE) Division
Semiconductor and Material Spectroscopy (SMS) Laboratory
KAUST Grant Number
BAS/1/1319-01-01Date
2020-10Online Publication Date
2020-10Print Publication Date
2020-10Embargo End Date
2021-10-02Submitted Date
2020-07-26Permanent link to this record
http://hdl.handle.net/10754/665425
Metadata
Show full item recordAbstract
High-energy radiation detectors such as X-ray detectors with low light photoresponse characteristics are used for several applications including, space, medical, and military devices. Here, an indirect bandgap inorganic perovskite-based X-ray detector is reported. The indirect bandgap nature of perovskite materials is revealed through optical characterizations, time-resolved photoluminescence (TRPL), and theoretical simulations, demonstrating that the differences in temperature-dependent carrier lifetime related to CsPbX3 (X = Br, I) perovskite composition are due to the changes in the bandgap structure. TRPL, theoretical analyses, and X-ray radiation measurements reveal that the high response of the UV/visible-blind yellow-phase CsPbI3 under high-energy X-ray exposure is attributed to the nature of the indirect bandgap structure of CsPbX3. The yellow-phase CsPbI3-based X-ray detector achieves a relatively high sensitivity of 83.6 μCGyair−1 cm−2 (under 1.7 mGyair s−1 at an electron field of 0.17 V μm−1 used for medical diagnostics) although the active layer is based solely on an ultrathin (≈6.6 μm) CsPbI3 nanocrystal film, exceeding the values obtained for commercial X-ray detectors, and further confirming good material quality. This CsPbX3 X-ray detector is sufficient for cost-effective device miniaturization based on a simple design.Citation
Xin, B., Alaal, N., Mitra, S., Subahi, A., Pak, Y., Almalawi, D., … Roqan, I. S. (2020). Identifying Carrier Behavior in Ultrathin Indirect-Bandgap CsPbX3 Nanocrystal Films for Use in UV/Visible-Blind High-Energy Detectors. Small, 2004513. doi:10.1002/smll.202004513Sponsors
This work was financially supported by the King Abdullah University of Science and Technology (KAUST) baseline funding (BAS/1/1319-01-01). The authors thank the KAUST Medical Center (KMC) located at the KAUST campus for providing their X-ray facilities for carrying out the measurements.Publisher
WileyJournal
SmallAdditional Links
https://onlinelibrary.wiley.com/doi/10.1002/smll.202004513ae974a485f413a2113503eed53cd6c53
10.1002/smll.202004513