Undoped and Tl-Doped Cs3Cu2I5 Thin Films as Potential X-ray Scintillators

0D halide perovskite Cs3Cu2I5-based nanocrystals and bulk crystals are proven to be sensitive and efficient scintillators for X-ray and gamma-ray detection. Herein, undoped and Tl-doped Cs3Cu2I5 microcrystalline films are synthesized by a thermal evaporation method. Both films crystallize into a Pnma space group of orthorhombic crystal lattice with preferred (004) growth orientation. The undoped Cs3Cu2I5 thin film shows a sole emission peaking at 440 nm associated with the self-trapped exciton emission. Doping of Tl+ ions introduces another emission that peaks at 520 nm. The scintillation efficiency of both undoped and Tl-doped Cs3Cu2I5 thin films is about one-third of that of CsI:Tl thin film with the same size and thickness. Within the first 5 s after X-ray cutoff, afterglow signals of both the undoped and Tl-doped Cs3Cu2I5 thin films are over one order of magnitude lower than that of CsI:Tl thin film.

Automated summary

Halide perovskite Cs3Cu2I5-based nanocrystals and bulk crystals have been shown to be sensitive and efficient scintillators for X-ray and gamma-ray detection. Undoped and Tl-doped Cs3Cu2I5 microcrystalline films were synthesized and both exhibited lower scintillation efficiency compared to CsI:Tl thin film, but with afterglow signals significantly lower.