人工晶体学报2026，Vol.55Issue(5)：689-696,8.DOI:10.16553/j.cnki.issn1000-985x.2026.0008
大尺寸钙钛矿CsPbBr3单晶生长和γ射线探测性能研究
Growth and γ-Ray Detection Performances of Large-Sized Perovskite CsPbBr3 Single Crystals
摘要
Abstract
Semiconductor radiation detectors have broad and surging applications in homeland security,medical imaging,and fundamental scientific research.Recently,the all-inorganic perovskite CsPbBr3 has attracted considerable attention owing to its suitable bandgap(～2.3 eV),high effective atomic number(65.9),high density(4.85 g·cm3),high resistivity(＞109 Ω·cm),and excellent carrier transport properties(μτ on the order of 10-3 cm2·V-1),making it a promising candidate for next-generation room-temperature semiconductor radiation detectors.Specifically,CsPbBr3 crystals can be synthesized via either solution-growth or melt-growth techniques.Solution-based methods are typically carried out at relatively low temperatures and feature simple fabrication procedures and low cost.However,the size of solution-grown CsPbBr3 crystals is generally limited to the centimeter scale.In comparison,melt-growth techniques are currently the most widely used methods for producing large-size CsPbBr3 crystals.Nevertheless,melt growth is typically carried out at high temperatures using high-purity raw materials.Moreover,due to the relatively low thermal conductivity of CsPbBr3,together with the structural phase transitions during the cooling process,defects such as twins and cracks are readily generated,severely deteriorating the single-crystal quality and detector performance. In this work,the growth process of CsPbBr3 crystals was systematically investigated using the vertical Bridgman method.Based on optimized growth parameters,including the temperature gradient and cooling rate,a high-quality large-volume CsPbBr3 crystal with dimensions of φ40 mm×7 cm was successfully grown using zone-refined CsPbBr3 polycrystals.The optical properties of the as-grown CsPbBr3 crystals were systematically characterized.UV-Vis-NIR measurement revealed a high optical transmittance of up to 80％and a bandgap of 2.27 eV.Photoluminescence(PL)measurement showed a strong emission peak at 531 nm,while time-resolved photoluminescence(TRPL)spectra exhibited decay lifetimes of 2.26 and 38.62 ns,respectively.To evaluate the electrical properties,γ-ray detection performance,and charge transport properties,an asymmetric Au/CsPbBr3/EGaIn planar device was fabricated.The CsPbBr3 detector exhibited a high resistivity of up to 6.12×109Ω·cm determined by current-voltage(I-V)test.Owing to the asymmetric Schottky-type configuration,the dark current was effectively suppressed to 4.4 nA at-100 V,which was approximately two orders of magnitude lower than that measured at 100 V.In addition,the device exhibited a large ON/OFF ratio of 2 300 under a bias of-10 V using a white LED as the illumination source during current-time(I-t)test.The detector was subsequently evaluated using various γ-ray sources under a hole-dominant collection mode,achieving energy resolutions(ERs)of 10.0％,5.5％,and 1.6％at room temperature for 241Am(59.5 keV),57Co(122 keV),and 137Cs(662 keV)γ-rays,respectively.Carrier transport properties,particularly high carrier mobility and long carrier lifetime,are critical for improving charge collection efficiency and radiation detection performance.Using a 241 Am γ-ray source,the hole mobility of CsPbBr3 was determined to be 24.41 cm2·V-1·s-1 via time-of-flight(TOF)measurement,while the hole mobility-lifetime product was extracted to be 4.17×10-3 cm2·V-1based on the Hecht equation.This work presents a reliable growth process for producing high-quality large-volume perovskite CsPbBr3 with superior radiation detection performance,which may facilitate their scalable fabrication and practical applications.关键词
全无机钙钛矿CsPbBr3/坩埚下降法/半导体核辐射探测器/γ射线探测/载流子输运性能/能量分辨率Key words
all-inorganic perovskite CsPbBr3/Bridgman method/semiconductor radiation detector/γ-ray detection/carrier transport property/energy resolution分类
天文与地球科学引用本文复制引用
杜峻,汪俞权,肖宝,孙啟皓,申南南,何亦辉..大尺寸钙钛矿CsPbBr3单晶生长和γ射线探测性能研究[J].人工晶体学报,2026,55(5):689-696,8.基金项目
国家自然科学基金(U2267211) （U2267211）
国家重点研发计划(2021YFF0502600) （2021YFF0502600）
江苏省自然科学青年基金(BK20240822) （BK20240822）
苏州市创新创业领军人才计划项目(ZXL2022455) （ZXL2022455）
集成光电子学国家重点实验室开放课题(IOSKL2025KF06) （IOSKL2025KF06）
功能晶体与器件全国重点实验室开放课题(SKLFCD202501SIC) （SKLFCD202501SIC）
苏州大学大学生创新创业训练计划(202410285089Z) （202410285089Z）
