Ce3+掺杂CsPbBr3纳米晶的制备与性能

采用热注入法制备Ce³⁺掺杂CsPbBr₃纳米晶,利用XRD、TEM、XPS、UV-Vis、PL、Time-resolved fluorescence spectroscopy、J-V曲线测试等对样品的晶体结构、微观形貌、化学组成、光吸收性能、发光性能、荧光寿命和荧光太阳能集光器(LSC)的光学效率进行表征。实验结果表明:采用热注入法成功制备出分散性良好、平均晶粒大小为12.26 nm的立方相Ce³⁺掺杂CsPbBr₃纳米晶。Ce³⁺掺杂CsPbBr₃纳米晶的光学带隙和荧光发射峰强度随着Ce/Pb摩尔比的增加呈现先增大后减小的变化趋势,当n(Ce)/n(Pb)=0.25时,光学带隙达到最大为2.416 eV,发光强度最强,荧光发射峰由纯CsPbBr₃纳米晶的515 nm蓝移到510 nm,Ce³⁺掺杂CsPbBr₃纳米晶的发光性能与稳定性均得到增强。Ce³⁺掺杂CsPbBr₃纳米晶与聚苯乙烯溶液制备复合薄膜型LSC器件的光学效率ηopt最高达到6.81%。

Preparation and Properties of Ce3+ Doped CsPbBr3 Nanocrystals

The Ce³⁺ doped CsPbBr₃ nanocrystals were prepared by hot-injection method, the crystal phase structure, micro-morphology, chemical composition, light absorption performance, luminescence performance, fluorescence lifetime and optical efficiency of luminescent solar concentrators (LSC) devices were characterized by XRD, TEM, XPS, UV-Vis, PL, Time-resolved fluorescence spectroscopy and J-V curve test. The experimental results show that the cubic phase Ce³⁺-doped CsPbBr₃ nanocrystals with good dispersion and average grain size of 12.26 nm are successfully prepared by hot-injection method. The optical band gap and fluorescence emission peak intensity of Ce³⁺ doped CsPbBr₃ nanocrystals shows a trend of increasing and then decreasing with the increase of Ce/Pb molar ratio. When n(Ce)/n(Pb)=0.25, the optical band gap reaches a maximum of 2.416 eV, the luminescence intensity is the strongest, and the fluorescence emission peak blue-shifts from 515 nm to 510 nm for pure CsPbBr₃ nanocrystals. The luminescence performance and stability of Ce³⁺ doped CsPbBr₃ nanocrystals are enhanced. The optical efficiency ηopt of Ce³⁺ doped CsPbBr₃ nanocrystals with polystyrene solution for the preparation of composite thin-film LSC is up to 6.81%.