In-situ Light-Induced Halide Diffusion and Structural Dynamics in Amino Acid-Incorporated Lead-Halide Perovskites

Lead-halide hybrid perovskites (RNH3PbX3, X = halide) are promising for next-generation optoelectronic devices due to their strong light absorption and photoluminescence. However, interfacial halide diffusion often leads to mixed alloys, compromising sharp interfaces. To address this, we used a bio-inspired approach by incorporating amino acids into MAPbBr3 crystals. Preliminary findings in a previous experiment showed that Lys significantly slows Cl and I diffusion, stabilizing the perovskite structure. Additionally, light-induced halide segregation and re-mixing were observed, with diffraction peak shifts during and after UV illumination influenced by Lys incorporation. This proposal aims to further investigate halide diffusion, segregation, and vacancy formation using in-situ UV and HR-PXRD analysis at ID22, providing insights for improved material control in optoelectronics.