Narrow Linewidth Excitonic Emission in Organic-Inorganic Lead Iodide Perovskite Single Crystals

作者：Diab Hiba; Trippe Allard Gaelle; Ledee Ferdinand; Jemli Khaoula; Vilar Christele; Bouchez Guillaume; Jacques Vincent L R; Tejeda Antonio; Even Jacky; Lauret Jean Sebastien; Deleporte Emmanuelle; Garrot Damien

来源：Journal of Physical Chemistry Letters, 2016, 7(24): 5093-5100.

DOI：10.1021/acs.jpclett.6b02261

Hybrid perovskite thin films have demonstrated impressive performance for solar energy conversion and optoelectronic applications. However, further progress will benefit from a better knowledge of the intrinsic photophysics of materials. Here, the temperature-dependent emission properties of CH3NH3PbI3 single crystals are investigated and compared to those of thin polycrystalline films by means of steady-state and time-resolved photoluminescence spectroscopy. Single crystals photoluminescence present a sharp excitonic emission at high energy, with full width at half maximum of only 5 meV, assigned to free excitonic recombination. We highlight a strong thermal broadening of the free excitonic emission, due to exciton-LO-phonon coupling. The emission turned to be very short-lived with a subnanosecond dynamics, mainly induced by the fast trapping of the excitons. The free excitonic emission is completely absent of the thin film spectra, which are dominated by trap state bands.

• 出版日期2016-12-15