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.