Simultaneous Characterization of Optical, Electronic, and Thermal Properties of Perovskite Single Crystals Using a Photoacoustic Technique

Metal halide perovskite possesses many excellent properties beneficial to its potential applications in optoelectronics and pyroelectricity. Surface recombination velocity, electronic diffusivity, and excess carrier lifetime accounting for the photoexcited carrier recombination and electronic transport features are key for improving the performance of perovskite-based optoelectronic devices. Meanwhile, the thermal conductivity and thermal diffusivity in halide perovskite have been paid limited attention despite their potential practical applications such as heat management and thermoelectric materials. To date, lots of techniques have been developed to extract these physical properties, while very few of them can effectively and nondestructively receive the results. The photoacoustic (PA) technique based on photothermal conversion is a powerful method to study the optical, electronic, and thermal properties of various materials, especially semiconductor materials. Optical absorption spectrum, surface recombination velocity, electronic diffusivity, photoexcited carrier lifetime, and thermal diffusivity can be obtained simultaneously without the destruction and contact of the samples. Here, for the first time, we utilized the PA technique in the perovskite single crystal. Optical absorption of MAPbBr3 and MAPbI3 (MA = methylammonium) single crystals was investigated under a reflection detection configuration (RDC), and the electronic and thermal properties were measured under a transmission detection configuration (TDC). Comparing the results with previous reports and other characterizations, the PA technique has been verified to be an efficient and convenient method to study the optical, electronic, and thermal properties of perovskite single crystals