Ultrathin, Transparent, and High Density Perovskite Scintillator Film for High Resolution X‐Ray Microscopic Imaging

Abstract

Inorganic perovskite quantum dots CsPbX3 (X = Cl, Br, and I) has recently received extensive attention as a new promising class of X‐ray scintillators. However, relatively low light yield (LY) of CsPbX3 and strong optical scattering of the thick opaque scintillator film restrict their practical applications for high‐resolution X‐ray microscopic imaging. Here, the Ce3+ ion doped CsPbBr3 nanocrystals (NCs) with enhanced LY and stability are obtained and then the ultrathin (30 µm) and transparent scintillator films with high density are prepared by a suction filtration method. The small amount Ce3+ dopant greatly enhances the LY of CsPbBr3 NCs (about 33 000 photons per MeV), which is much higher than that of bare CsPbBr3 NCs. Moreover, the scintillator films made by these NCs with high density realize a high spatial resolution of 862 nm thanks to its thin and transparent feature, which is so far a record resolution for perovskite scintillator‐based X‐ray microscopic imaging. This strategy not only provides a simple way to increase the resolution down to nanoscale but also extends the application of as‐prepared CsPbBr3 scintillator for high resolution X‐ray microscopic imaging.

High quality lead-free perovskites toward white light emitting diodes and X-ray imaging

“…Lead halide perovskites CsPbX 3 (X = Cl − , Br − , and I − ) have emerged as a promising class of semiconducting materials due to their exceptional optoelectronic properties for optoelectronic applications, such as humidity sensors, 1 solar concentrators, 2 photocatalytic, 3 white light emitting diodes (WLEDs) 4,5 and X-ray imaging. 6,7 However, the toxicity and stability problems of lead halide perovskites hinder their practical application for long-term operation. 8 Hence, the exploration of lead-free perovskites with high-performance has attracted particular attention based on the substitution of Pb 2+ ions with nontoxic metal elements (Sn 2+ , 9 Ge 2+ , 10 Mn 2+ , 11 Bi 3+ , 12 In 3+ , 13 and Sb 3+ 14–16 ).…”

Competing Energy Transfer-Modulated Dual Emission in Mn2+-Doped Cs2NaTbCl6 Rare-Earth Double Perovskites

“…Lead halide perovskites of ABX 3 (A = MA + , Cs + ; B = Pb 2+ , X = Cl – , Br – , I – ) have been widely studied due to their promising optoelectronic applications such as such as solar cells, − light-emitting diodes, − lasers, − X-ray detectors, − and scintillators. , However, lead-based halide perovskites are often unstable and easily hydrolyzed. − Meanwhile, the toxicity of lead limits their applications . Thus, it is urgent to develop alternative lead-free perovskites with photoelectric properties similar to those of lead-based perovskites.…”

Micrometer-Resolution X-ray Imaging Enabled by a Flexible Perovskite Screen

“…Perovskite scintillator has emerged as a promising candidate for X-ray screen applications due to its heavy-atomic constituent, high light yield, and tunable wavelength. − In specific, perovskite polycrystalline film has demonstrated great potential in dynamic X-ray imaging with a low dose rate. , One major caveat of polycrystalline films was the tedious fabrication procedure which involved particle grinding, binder mixing, and slurry casting. − Despite its scalability for large-size screen, such an approach compromised on the flatness and thickness control over the scintillating layer, hindering further improvement of spatial resolution.…”