Surfactant-Dependent Bulk Scale Mechanochemical Synthesis of CsPbBr3 Nanocrystals for Plastic Scintillator-Based X-ray Imaging

Joydip Ghosh; Joseph O'Neill; Mateus G Masteghin; Isabel Braddock; Carol Crean; Robert Dorey; Hayden Salway; Miguel Anaya; Justin Reiss; Douglas Wolfe; Paul Sellin

doi:10.1021/acsanm.3c02531

Surfactant-Dependent Bulk Scale Mechanochemical Synthesis of CsPbBr₃ Nanocrystals for Plastic Scintillator-Based X-ray Imaging

ACS Appl Nano Mater. 2023 Aug 7;6(16):14980-14990. doi: 10.1021/acsanm.3c02531. eCollection 2023 Aug 25.

Authors

Joydip Ghosh¹, Joseph O'Neill¹, Mateus G Masteghin², Isabel Braddock¹, Carol Crean³, Robert Dorey⁴, Hayden Salway⁵, Miguel Anaya^{5

6}, Justin Reiss⁷, Douglas Wolfe⁷, Paul Sellin¹

Affiliations

¹ Department of Physics, University of Surrey, Guildford GU2 7XH, U.K.
² Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, U.K.
³ Department of Chemistry, University of Surrey, Guildford GU2 7XH, U.K.
⁴ School of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, U.K.
⁵ Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, U.K.
⁶ Departamento Física de la Materia Condensada, Instituto de Ciencia de Materiales de Sevilla, Universidad de Sevilla-CSIC, Avenida Reina Mercedes SN, Sevilla 41012, Spain.
⁷ Applied Research Laboratory, Materials Science and Engineering Department, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.

Abstract

We report a facile, solvent-free surfactant-dependent mechanochemical synthesis of highly luminescent CsPbBr₃ nanocrystals (NCs) and study their scintillation properties. A small amount of surfactant oleylamine (OAM) plays an important role in the two-step ball milling method to control the size and emission properties of the NCs. The solid-state synthesized perovskite NCs exhibit a high photoluminescence quantum yield (PLQY) of up to 88% with excellent stability. CsPbBr₃ NCs capped with different amounts of surfactant were dispersed in toluene and mixed with polymethyl methacrylate (PMMA) polymer and cast into scintillator discs. With increasing concentration of OAM during synthesis, the PL yield of CsPbBr₃/PMMA nanocomposite was increased, which is attributed to reduced NC aggregation and PL quenching. We also varied the perovskite loading concentration in the nanocomposite and studied the resulting emission properties. The most intense PL emission was observed from the 2% perovskite-loaded disc, while the 10% loaded disc exhibited the highest radioluminescence (RL) emission from 50 kV X-rays. The strong RL yield may be attributed to the deep penetration of X-rays into the composite, combined with the large interaction cross-section of the X-rays with the high-Z atoms within the NCs. The nanocomposite disc shows an intense RL emission peak centered at 536 nm and a fast RL decay time of 29.4 ns. Further, we have demonstrated the X-ray imaging performance of a 10% CsPbBr₃ NC-loaded nanocomposite disc.