Cesium-iodide-based nanocrystal for the detection of ionizing radiation

•The synthesis of CsI nanocrystal was studied using sol-gel technique.•The structural properties of CsI nanoparticles were studied by X-ray diffraction.•Optical properties were followed by optical absorption and UV–vis fluorescence.•The size effect on CsI luminescence leads to a good scintillation light yield.•The scintillation spectra to alpha particles of sample were studied.

We report on the synthesis of cesium-iodide nanoparticles using sol-gel technique. The structural properties of CsI nanoparticles were characterized by X-ray diffraction and optical properties were followed by optical absorption and UV–vis fluorescence. Intense photoluminescence is also observed, with some spectral tuning possible with ripening time getting a range of emission photon wavelength approximately from 366 to 350 nm. The size effect on CsI luminescence leads to an increase in scintillation light yield, a redshift of the emission bands of the on_center and off_center self_trapped excitons (STEs) and an increase in the contribution of the off_center STEs to the net intrinsic emission yield. The energy transfer from the matrix to CsI nanoparticles is a key characteristic for scintillation detectors. So the scintillation spectra and decay curve to alpha particles of sample were monitored.