Piezoelectric Charge Coefficient of Halide Perovskites

Halide perovskites are an emerging family of piezoelectric and ferroelectric materials. These materials can exist in bulk, single-crystal, and thin-film forms. In this article, we review the piezoelectric charge coefficient (d(ij)) of single crystals, thin films, and dimension-tuned halide perovskites based on different measurement methods. Our study finds that the (d(ij)) coefficient of the bulk and single-crystal samples is mainly measured using the quasi-static (Berlincourt) method, though the piezoforce microscopy (PFM) method is also heavily used. In the case of thin-film samples, the (d(ij)) coefficient is dominantly measured by the PFM technique. The reported values of d(ij) coefficients of halide perovskites are comparable and even better in some cases compared to existing materials such as PZT and PVDF. Finally, we discuss the promising emergence of quasi-static methods for thin-film samples as well.