Engineering Electrooptical Properties of 2 Dimensional Hybrid Perovskites with Pressure

Hybrid perovskites are a new class of functional materials with potential applications in various technologically important areas, such as solar cells, LED and lasing. Compared with their 3D counterparts, 2 dimensional perovskites exhibit special properties, e.g. their natural quantum-well structure yields stable excitons, able to interact more strongly with phonons, spins and defects. Layered perovskites are also more structurally stable.

High pressure induces a rich variety of phenomena in the electronic and optical properties in the hybrid Perovskite materials, including enhancement of photoluminescence (PL) by at least two orders of magnitude, narrow to white light emission, rich PL energy and lifetime changes. The optical properties of 2D perovskites are mainly governed by excitons, and the investigation of intrinsic and extrinsic, radiative and nonradiative exciton recombination pathways is essential. Lattice vibrations create spatial and temporal potential fluctuations, that governs exciton-phonon interactions. In this talk, I will illustrate how high pressure can be used to tune the electrooptical properties of the hybrid perovskite materials, and how such study can provide some guidance in the synthesis of new materials.