Photoluminescence and scintillation characteristics of (C <sub>6</sub> H <sub>5</sub> C <sub> <i>n</i> </sub> H <sub> 2 <i>n</i> </sub> NH <sub>3</sub> ) <sub>2</sub> PbBr <sub>4</sub> ( <i>n</i> = 2, 3, 4)
Ryo Nagaoka, Naoki Kawano, Daisuke Nakauchi, Hiromi Kimura, Masaki Akatsuka, Takayuki Yanagida
Abstract
Abstract We prepared crystals of (C 6 H 5 C n H 2 n NH 3 ) 2 PbBr 4 ( n = 2, 3, 4), and evaluated their photoluminescence and scintillation characteristics. According to the photoluminescence spectra under 340 nm excitation light, a photoluminescence peak at around 410 nm due to free exciton emissions appeared in (C 6 H 5 C 2 H 4 NH 3 ) 2 PbBr 4 (2PEA), (C 6 H 5 C 3 H 6 NH 3 ) 2 PbBr 4 (3PPA) and (C 6 H 5 C 4 H 8 NH 3 ) 2 PbBr 4 (4PBA). The quantum efficiencies of 2PEA, 3PPA and 4PBA were 0.24, 0.01 and 0.04, respectively. In scintillation, a sharp scintillation peak originating from the exciton emissions was detected at approximately 436 nm for 2PEA, 459 nm for 3PPA and 442 nm for 4PBA. In addition, the scintillation light yield of 4PBA under 59.5 keV gamma-ray irradiation from 241 Am was determined to be approximately 2200 photons MeV −1 in comparison with the yield of 2PEA (14 000 photons MeV −1 ), whereas the yield of 3PPA could not be determined due to its low scintillation intensity.