From Optoelectronics to Radiation Detection: Light Yield Challenges in Perovskite Scintillators.

The emergence of nanomaterials, such as lead halide perovskites (LHPs), has catalyzed the development of next-generation scintillators based on thin films and nanocrystals for radiation detection. While these materials offer unique advantages in terms of scalability, emission tunability, and fabrication versatility, accurately quantifying their light yield (LY) remains a fundamental yet unresolved challenge. Unlike bulk crystals, thin films suffer from reduced energy deposition, complex optical and luminescence loss mechanisms, and geometry-dependent light extractionall of which can severely distort LY measurements. In this Perspective, we highlight the critical methodological limitations of current LY characterization approaches when applied to emerging LHP scintillators. We discuss the theoretical framework underpinning LY, the pitfalls of using traditional bulk-based protocols, and the need for precise energy deposition modeling. Finally, we propose practical guidelines for achieving reproducible, accurate LY determinations in thin-film or nanocomposite formats, thereby enabling a fair comparison across materials and facilitating the development of high-performance scintillators for emerging radiation detection technologies.