High Photoluminescence Quantum Yield Perovskite/Polymer Nanocomposites for High Contrast X-ray Imaging.

A surface modified-CsPbBr/polybutylmethacrylate (PBMA) nanocomposite is reported to be a scintillator that enables us to provide a high contrast X-ray image using a common charge-coupled device (CCD) camera. Bis(2-(methacryloyloxy)ethyl) phosphate (BMEP) was employed to alter the ratio of the original ligands on the CsPbBr nanocrystal (NC) surface for optimizing the optical performance of the CsPbBr/PBMA nanocomposites. The nanocomposites with a concentration of 0.02 wt % NCs exhibit more than 70% transmittance in the visible region and show a green emission at 515 nm, the fast decay time is 13 ns, while the photoluminescence quantum yield value is 99.2%. Under X-ray excitation, the emission peak wavelength is centered at 524 nm and shows a narrow full width at half-maximum of 26.6 nm; the result nicely matches with the peak quantum efficiency of most commercial CCD/complementary metal oxide semiconductor cameras. The high contrast X-ray image is recorded at a low dose rate of 4.6 μGy/s, which enables read out with software. Our results demonstrate that these CsPbBr/PBMA nanocomposites have promising application prospects for ionizing radiation detection, especially for X-ray imaging.