Tissue equivalent curved organic X‐ray detectors utilizing high atomic number polythiophene analogues
Abstract
Organic semiconductors are a promising material candidate for X-ray detection. However, the low atomic number (Z) of organic semiconductors leads to poor X-ray absorption thus restricting their performance. Herein, the authors propose a new strategy for achieving high-sensitivity performance for X-ray detectors based on organic semiconductors modified with high –Z heteroatoms. X-ray detectors are fabricated with p-type organic semiconductors containing selenium heteroatoms (poly(3-hexyl)selenophene (P3HSe)) in blends with an n-type fullerene derivative ([6,6]-Phenyl C71 butyric acid methyl ester (PC70BM). When characterized under 70, 100, 150, and 220 kVp X-ray radiation, these heteroatom-containing detectors displayed a superior performance in terms of sensitivity up to 600 ± 11 nC Gy−1 cm−2 with respect to the bismuth oxide (Bi2O3) nanoparticle (NP) sensitized organic detectors. Despite the lower Z of selenium compared to the NPs typically used, the authors identify a more efficient generation of electron-hole pairs, better charge transfer, and charge transport characteristics in heteroatom-incorporated detectors that result in this breakthrough detector performance. The authors also demonstrate flexible X-ray detectors that can be curved to a radius as low as 2 mm with low deviation in X-ray response under 100 repeated bending cycles while maintaining an industry-standard ultra-low dark current of 0.03 ± 0.01 pA mm−2.
Citation
Nanayakkara , M P A , He , Q , Ruseckas , A , Karalasingam , A , Matjacic , L , Masteghin , M G , Basiricò , L , Fratelli , I , Ciavatti , A , Kilbride , R C , Jenatsch , S , Parnell , A J , Fraboni , B , Nisbet , A , Heeney , M , Jayawardena , K D G I & Silva , S R P 2023 , ' Tissue equivalent curved organic X‐ray detectors utilizing high atomic number polythiophene analogues ' , Advanced Science , vol. Early View , 2304261 . https://doi.org/10.1002/advs.202304261
Publication
Advanced Science
Status
Peer reviewed
ISSN
2198-3844Type
Journal article
Description
Funding: K.D.G.I.J., and S.R.P.S. gratefully acknowledge support from SilverRay Ltd. and EPSRC for this work (EP/R025304/1). M.P.A.N. acknowledges support from Advanced Technology Institute & DoC-CAT studentship, University of Surrey. M.G.M. acknowledges support from the University of Surrey/Advanced Technology Institute via URS/ORS studentship. M.G.M acknowledges support from the Engineering and Physical Research Council (Grant number EP/V036327/1). K.D.G.I.J. acknowledges support from the Equality Foundation of Hong Kong and the Royal Society (RGS∖R1∖211403). L.B., A.C., I.F. and B.F. acknowledge funding from INFN through the CSN5 FIRE project. M.H. acknowledges support from Royal Society and the Wolfson Foundation (Royal Society Wolfson Fellowship).Collections
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