Low temperature synthesis of CsPbI3 sub-micrometer wires with tailored emission band for flexible X-ray phosphors applications

CsPbI3 sub-micrometer wires were synthesized by one-pot solution method at near room temperature. The wires are single crystalline with [100] orientation. An strong emission band centered at 470 nm was observed under ultraviolet excitation, and the emission intensity and bandwidth are dependent on the molar ratio of CsI/PbI2 in the wires. A bright green emission with a lifetime of several tens ns was observed when excited with a soft X-ray, and the spectral response range can be modulated by the molar ratio of CsI/PbI2 in the wires. The growth mechanism of the wires was discussed, and the influences of the cycling strain and X-ray irrigation time on the X-ray excited optical luminescence of the CsI/PbI2 wires/PET film were analyzed and discussed.