Development and characterisation of caesium lead halide perovskite nanocomposite scintillators for X-ray detection

Abstract

We present work on the development of mixed-halide perovskite (CsPbClxBr(1−x)) nanocrystal scintillators for X-ray detection applications. The effect of the varying the halide composition on the resulting peak emission and light yield is discussed, with the CsPbBr3 materials displaying the greatest light yield. These perovskite nanocrystals were successfully loaded into PMMA, an inert plastic, at 2% mass weighting and the responses of these composites were compared to that of their colloidal dispersions. The composites were also characterised in terms of the radioluminescent light yield and decay response, alongside their X-ray sensitivity, in which the PMMA-CsPbBr3 composites again outperformed the materials containing Cl− anions.

Advances in Perovskite Nanocrystals and Nanocomposites for Scintillation Applications

“…This also offers the possibility of using these powders as building blocks for higher order materials. − Alternatively, in situ synthesis of PNCs directly within the matrix or intercalation of previously synthesized PNCs is used to obtain polymeric coatings. This method allows the production of homogeneous thin nanocomposites (up to hundreds of μm), which are typically used as screens for X-ray imaging, − an application that does not require large thicknesses but does require high precision. Finally, massive nanocomposites for applications in high-energy physics and/or rare event detection are typically obtained using bulk polymerization techniques. , All these strategies adopted to obtain powders, coatings, and bulk scintillators are schematically shown in Figure and described in details in the following sections, with particular emphasis on preserving, or even improving, the scintillating properties of PNC emitters once embedded in polymeric matrices, , which represents the most challenging aspect of nanocomposite fabrication.…”

“…Moreover, photostability was observed to be greatly enhanced in the polymer-encapsulated PNCs, which could sustain over 10 10 absorption events per PNC prior to photodegradation. This strategy has been used in many explorative studies of the scintillation properties of PNCs, such as the work on scintillation timing by Čuba and co-workers − described in detail below and by the Sellin group using mixed-halide CsPbCl x Br (1– x ) PNCs in PMMA and FAPbBr 3 PNCs in PMMA and PVT matrixes . Also using the solvent evaporation method, Gandini et al produced PMMA nanocomposites incorporating both CsPbBr 3 PNCs and a large Stokes shift perylene dyad with optical absorption resonant to the emission of PNCs, which resulted in sensitized RL free from reabsorption losses.…”

Recent Advances and Opportunities in Low‐Dimensional Layered Perovskites for Emergent Applications beyond Photovoltaics

“…Based on their working principles, X-ray detectors can be specified into (a) Direct detectors, which absorb the X-ray photons and convert them into electrical current, (b) Indirect detector, which essentially contains a scintillator that converts higher energy Xray photons into lower energy photons in the UV/vis region which can be further detected by a photodetector array. [200][201][202]…”

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

“…Recently, metal halide perovskites have attracted a lot of attention due to their low-cost solution processable fabrication and impressive optoelectronic properties, with high X-ray absorption coefficient, large electron–hole diffusion lengths, tunable emission wavelength, etc. − All-inorganic metal halide perovskites including CsPbBr 3 nanocrystals (NCs) exhibit an excellent range of optical properties including high photoluminescence quantum yield (PLQY), narrow PL full-width at half-maxima (FWHM), high photostability, and superior performance as light-emitting diodes (LEDs) . Recently, all-inorganic perovskite NCs have emerged as promising scintillating materials due to their efficient radioluminescence (RL) emission, high X-ray attenuation, and low detection limit. − The nanocomposite plastic scintillator, in which high-Z nanoparticles with high emission are added to a plastic, has great potential for ionizing radiation detection and imaging . However, these NCs are difficult to cast uniformly into compact solid or composite films, and emission quenching is often observed due to self-assembly and spontaneous aggregation, particularly at high mass loading …”