[19a-E204-1~11] 3.1 Basic optics and frontier of optics

[19a-E204-5] Tuning of Band Gaps in Lead Halide Perovskites by Anion Exchange Reactions under Focused Laser Irradiation

〇Kenichi Yuyama^1,2, Md Shahjahan², Md Jahidul Islam², Vasudevanpillai Biju^1,2 (1.Hokkaido Univ. RIES, 2.Hokkaido Univ. Env. Sci.)

Keywords:perovskite, laser trapping, halogen exchange reaction

Organic-inorganic lead halide perovskites have attracted extensive attention due to their potential application to solar cells, lasers, light-emitting diodes, photodetectors, and so on. They efficiently absorb visible to near-infrared light, and show brilliant photo- and electro- luminescence, long-range diffusion of electrons and holes, which are in addition to simple, low-temperature solution processing. Optical and electronic properties of perovskite crystals can be modified by tuning their band gaps. Halide exchange reaction is a post-synthesis approach for the band gap tuning. In general, the exchange reaction is induced by exposing perovskite crystals to the solution containing reactant halide ions, and the band gap is homogeneously varied in the whole crystals. Here, we demonstrate site-specific halide exchange reaction with the use of a focused laser beam.