Details

Autor(en) / Beteiligte

• Han, Lili
• Sun, Beibei
• Guo, Chao
• Peng, Guoqiang
• Chen, Huanyu
• Yang, Zhou
• Li, Nan
• Ci, Zhipeng
• Jin, Zhiwen

Titel

Photophysics in Zero‐Dimensional Potassium‐Doped Cesium Copper Chloride Cs 3 Cu 2 Cl 5 Nanosheets and Its Application for High‐Performance Flexible X‐Ray Detection

Ist Teil von

• Advanced optical materials, 2022-03, Vol.10 (6)

Erscheinungsjahr

2022

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Abstract Zero‐dimensional Cs 3 Cu 2 Cl 5 exhibits intriguing optical properties, which can meet the basic requirements of ideal scintillator application. Here, green emitter Cs 3 Cu 2 Cl 5 nanosheets are successfully synthesized, and by doping with 2% potassium (K + ), their photoluminescence quantum yield (70.23% to 81.39%), radioluminescence intensity, and stability are improved. Further experimental and theoretical studies point out that: (1) K + brings the neighboring [Cu 2 Cl 5 ] 3− dimers groups closer, leading to lattice shrinkage and lower lattice constants; (2) such compact crystal structure results in stronger exciton–photon coupling and reduced phonon–electron coupling strength, which is beneficial to form self‐trapped excitons and enhanced luminescence; (3) lower lattice constants also induce decreased bandgap (2.58 to 2.51 eV) and increased Stokes shift (217 to 223 nm), for less self‐absorption and higher quantum efficiency. Finally, area‐controllable uniform flexible Cs 3 Cu 2 Cl 5 :2%K + –polystyrene film is successfully achieved with excellent X‐ray sensibility. Such flexible film shows low cost (2.8223 $/g), broadband response (20–160 keV), and high spatial resolution (5 lp mm −1 ) that is comparable to commercial CsI:Tl wafer. Moreover, it fits well with nonplanar surfaces for high‐quality medical and industrial flexible images applications. It is believed that this work can provide a viable tactic to enhance X‐ray detection in metal halide scintillators.