Scintillation properties of composite films based on CsPbBr3 nanocrystals embedded in PMMA
Tamara Skrypnyk, O. Viahin, Iryna Bespalova, О. V. Zelenskaya, В. А. Тарасов, V. Alekseev, Svetlana Yefimova, Sorokin Av
Abstract
Transparent composite films of polymethylmethacrylate with embedded CsPbBr3 colloidal nanocrystals (CsPbBr3-PMMA) were obtained. The optical, photoluminescent, and scintillation properties of the composite films were studied. The CsPbBr3-PMMA films had an intense photoluminescence signal and a nanosecond-range photoluminescence decay time (2 ns). The scintillation characteristics of CsPbBr3-PMMA films of different thicknesses were studied upon excitation by α-radiation of radionuclides 239Pu (Eα = 5.15 MeV) and 238Pu (Eα = 5.46 MeV). The sensitivity and minimum detectable activity of the composite films were calculated from the pulse-height spectra. The estimation of the absolute light yield according to the IEC 62372:2021 standard (determining the intrinsic resolution of scintillator) and calculation of the light collection coefficient showed that the 200-μm thick composite film emitted about 860 photons per 1 MeV of absorbed energy. Under α-excitation, the films revealed a fast scintillation response with average decay time of about 1.4 ns.