Lead halide perovskites are renowned for their outstanding thermal properties. However, the potential in the photoacoustic field has been scarcely investigated due to some difficulties in theories and experiments. This paper establishes a theoretical model for the photoacoustic effect in MAPbI 3 perovskite films based on the photoacoustic theory of solids, considering both thermoelastic coupling and thermal conduction. Concurrently, the optical absorption coefficient of the MAPbI 3 film (10 4 − 10 5 cm −1 ) under pulsed illumination is incorporated, facilitating the derivation of an expression for the acoustic pressure of the photoacoustic signal. An acoustic platform is built to measure the output sound pressure generated by MAPbI 3 films on glass substrates, to compare theoretical predictions with corresponding experimental results. The findings reveal identical results between the two in the frequency domain. Furthermore, the output sound pressure of the films MAPbI 3 is found to exhibit a linear dependence on the input optical power, thus validating the proposed theoretical model. The effect of MAPbI 3 material thickness on light absorption and photoacoustic efficiency is also examined, providing both a theoretical foundation and experimental validation for the application of perovskite materials in photoacoustic devices.
Hu et al. (Sat,) studied this question.