Se4+ doped CsPbX3 (X=Cl/Br, Br, Br/I, I) perovskite quantum dot glasses for long wavelength pass filters with deep energy level quenching mechanism

CsPbX3 (X=Cl/Br, Br, Br/I, I) perovskite quantum dots (QDs) glasses have enormous application potential in the field of long wavelength pass (short wavelength cutoff) filters. In this work, the CsPbX3 (X=Cl/Br, Br, Br/I, I) QDs doped with Se4+ were prepared in the borogermanate glass matrix. To quench strong exciton emission of QDs, the CsPbX3 (X=Cl/Br, Br, Br/I, I) perovskite QDs glasses were doped with Se4+ at different concentrations of 0, 0.05%, 0.1% and 0.2%, respectively. The nanocrystal structure, transmittance, optical density, photoluminescence (PL), PL excitation and PL decay have been investigated. The working wavelength of filters has been extended to wide range from 440 nm to 650 nm. The samples have large optical density in cutoff region, excellent steepness in the transition region, and high transmittance in transmission region. As Se4+ concentration increases, the PL intensity is quenched and the PL lifetime is decreased obviously for CsPbX3 QDs glasses, whereas the absorption and transmittance characteristics for filters are less affected. The quenching mechanism is attributed to nonradiative recombination by deep energy level traps. The Se4+ doped CsPbX3 QDs glasses can meet requirements for the long wavelength pass filters.