 Lead-free parafskite nanocrystals, NCs, such as CS3CU2I5, can be used as highly sensitive and efficient scintillators due to their unique properties. These NCs emit bright blue light when exposed to X-rays, making them ideal for use in X-ray imaging applications. Additionally, they do not suffer from self-absorption, meaning that they produce more light than other scintillator materials. This makes them ideal for large area and flexible X-ray imaging. This article was authored by Lin Yuan Lian, Mo Yanzheng, Weizhuazhang, and others.