On the use of CdSe scintillating nanoplatelets as time taggers for high-energy gamma detection

Abstract

The technological challenge imposed by the time resolution essential to achieve real-time molecular imaging calls for a new generation of ultrafast detectors. In this contribution, we demonstrate that CdSe-based semiconductor nanoplatelets can be combined with standard scintillator technology to achieve 80 ps coincidence time resolution on a hybrid functional pixel. This result contrasts with the fact that the overall detector light output is considerably affected by the loss of index-light-guiding. Here, we exploit the principle of 511 keV energy sharing between a high-Z, high stopping power bulk scintillator, and a nano-scintillator with sub-1 ns radiative recombination times, aiming at a breakthrough in the combined energy and time resolution performance. This proof-of-concept test opens the way to the design and study of larger size sensors using thin nanocomposite layers able to perform as efficient time taggers in a sampling detector geometry of new generation. npj 2D Materials and Applications (2019) 3:37; https://doi.

Exploring Cherenkov Emission of BGO for TOF-PET

“…A prominent example is discussed in [16] having energy sharing of fast organic scintillators and inorganic scintillators giving various time resolutions depending on the energy deposition in the fast scintillator. Further improvement are expected when replacing the organic scintillator with nanostructures like CdSe [34] or CsPbBr 3 [35]. Another way to use the classification approach is by combining it with depth of interaction information (DOI) [36], as the time resolution changes depending on the DOI position [37].…”

Composite fast scintillators based on high-Z fluorescent metal–organic framework nanocrystals

“…Several strategies can be pursued for this aim, since by engineering the MOF nanocrystal composition we can increase its density, scintillation yield and radiative rate to boost performance. Examples include the incorporation of heavier elements such as hafnium, to enhance the interaction with the ionizing radiation and thus produce more photons, or coupling with high-density materials in unconventional heterostructures 10,11 . In addition, maximing the system PL quantum yield through better compatibilization of the nanocrystals with the host polymer has been foreseen 36 , as well as the use of self-absorption-free multi-emitter MOF nanocrystals with a large Stokes shift or the use of faster emitters.…”

“…The realization of new scintillators [9][10][11] will be decisive towards TOF-PET development since the commonly used bulk and nanostructured inorganic crystals 1 , organic chromophores and plastics 12 do not offer the synthetic versatility required to have full control over the properties affecting the time resolution, such as the quantum efficiency and the timing of the scintillator output 13 . This highlights the pioneering work by Allendorf and collaborators 14 , who demonstrated the scintillation of fluorescent MOFs.…”

Use of 2D Nanoplatelets to Improve The Sensitivity in Hybrid Photodetector For Indirect X-Ray Imaging

“…The organic/NCs hybrid semiconductors are suitable for large scale, easy fabrication processing, and physically exible devices [21] because of their solution processability. Therefore, they can be used as active materials in a variety of applications such as in light-emitting diodes (LEDs) [22], photodetectors [23], biomedical labelling [24], and radiation detectors [25]. Among these, in the eld of radiation detectors, hybrid active layer research with these organic/NCs hybrid semiconductors is underway with the goal of improving detection sensitivity [26,27].…”