Size Effect on X‐ray Scintillation Performance for Perovskite Nanocrystals Revealed by Mathematical Model

Abstract Nanoscintillators (nanocrystals with X‐ray scintillation performance) lay a fundamental for their practical application in high‐resolution and low‐dose medical examination due to their excellent photoelectric properties. The optical properties and scintillation performance of nanocrystals (NCs) can be significantly affected by adjusting their size. However, the mechanism of the size effect of NCs on optical properties and X‐ray scintillation performance has not been revealed. Here, a mathematical model and experimental results are combined to demonstrate the impact of the size of NCs on their scintillation performance. The results show that the surface area and volume of NCs exhibit a positive and negative impact on the change rate of the bandgap, respectively. This model further verifies that the photoluminescence quantum yield of NCs decreases with the decrease of their size, and their light yield is remarkably affected by the size of NCs. Overall, this work provides some enlightenment for researchers to design NCs with the appropriate size for their applications in high‐performance X‐ray scintillation.