Direct Detection of Fast Neutrons by Organic Semiconducting Single Crystal Detectors. (6th November 2021)

• Record Type: Journal Article
• Authors: Zhao, Dou; Cai, Pingkun; Cheng, Wei; Jia, Wenbao; Zhang, Binbin; Zhu, Menghua; Liu, Linyue; Ouyang, Xiaoping; Sellin, Paul; Jie, Wanqi; Xu, Yadong
• Is Part Of: Advanced functional materials. Volume 32:Number 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-11-06
• Subjects: cancer therapies -- direct fast neutron detector -- functional group tailoring -- neutron imaging -- neutron radiation damage mechanism -- organic semiconductors -- tissue‐equivalent dosemeter; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202108857
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Fast neutron detection is significant for neutron imaging and flux monitoring but cannot be directly achieved by inorganic semiconductors. The traditional detection is mainly mediated by an organic scintillator and a coupled photodetector, resulting in signal losses. Here, a direct detection method for fast neutrons is demonstrated based on organic semiconducting single crystals (OSSCs) detectors. Methyl 4‐hydroxybenzoate (4MHB, C6 H5 O‐COOCH3 ) and 4‐hydroxycyanobenzene (4HCB, C6 H5 O‐CN). The organic semiconductor acts as a fast neutron sensitive material due to its high hydrogen density, simultaneously as a semiconductor that generates the electric signal. The detectors based on 4MHB crystals can quantitatively measure the dose and energy of the fast neutron flux with a response time of 0.5 µs and detection efficiency of 78.5% cm −3 . Effects of functional groups on fast neutron detection performances are also investigated as a guideline to synthesis new molecules for this purpose. Furthermore, neutron radiation effects on these detectors are investigated. Hydrogen‐related point defects are generated by fast neutrons, but device performances remain robust after irradiation of 10 13 n cm −2 fast neutrons. This study demonstrates that OSSCs show great potential as direct fast neutron detectors and particularly have highly‐localized and tissue‐equivalent properties that benefit neutron imaging and cancer therapy applications. Abstract : Compact semiconducting detectors based on organic single crystals for direct fast neutron detection can quantitatively measure the dose and energy of incident fast neutron flux with a fast time response and a good radiation endurance, directly breaking the detector limitation for both high‐resolution fast neutron imaging and high‐localized and tissue‐equivalent dosimetry during cancer therapy.