Localized quenching sites in MAPbI3 investigated by fluorescence and photothermal microscopy

Weiqing Yang; Meilian Li; Mingcai Xie; Yan Nie; Anbang Du; Yuxi Tian

doi:10.1063/5.0048239

Localized quenching sites in MAPbI₃ investigated by fluorescence and photothermal microscopy

Rev Sci Instrum. 2021 Aug 1;92(8):083701. doi: 10.1063/5.0048239.

Authors

Weiqing Yang¹, Meilian Li¹, Mingcai Xie¹, Yan Nie¹, Anbang Du¹, Yuxi Tian¹

Affiliation

¹ Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, China.

PMID: 34470388
DOI: 10.1063/5.0048239

Abstract

In this work, we developed a fluorescence and photothermal microscope with extremely large scanning range and high spatial resolution. We demonstrated the capability of this instrument by simultaneously measuring the photoluminescence and photothermal signals of the CH₃NH₃PbI₃ (MAPbI₃) film. After scanning the MAPbI₃ film on the scale of centimeters, we can obtain information of both emissive and nonemissive processes with a resolution of 200 nm at any location of the large area. We can clearly see the localized photothermal signal while the photoluminescence signal is uniform. These results directly prove that the emissive recombination happens all over the materials, but the nonemissive recombination happens only at certain localized quenching sites. The fluorescence and photothermal microscope with both large scanning range and high spatial resolution can provide information of all the relaxation channels of the excitons, showing potential applications for investigation of photophysical mechanisms in photoelectric materials.