First-principles discovery of stable two-dimensional materials with giant piezoelectric response.

The rational design of two-dimensional piezoelectric materials has recently garnered great interest due to their increasing use in technological applications, including sensor technology, actuating devices, energy harvesting, and medical applications. Several materials possessing high piezoelectric response have been reported so far, but a high-throughput the first-principles approach to estimate the piezoelectric potential of layered materials has not been performed yet. In this study, we systematically investigated the piezoelectric (e11, d11) and elastic (C11 and C12) properties of 128 thermodynamically stable two-dimensional (2D) semiconductor materials by employing the first-principle methods. Our high-throughput approach demonstrates that the materials containing Group-V elements produce significantly high piezoelectric strain constants, d11 > 40 pm/V, and 49 of the materials considered have the e11 coefficient higher than MoS2 insomuch as BrSSb has one of the largest d11 with a value of 373.0 pm/V. Moreover, we established a simple empirical model in order to estimate the d11 coefficients by utilizing the relative ionic motion in the unit cell and the polarizability of the individual elements in the compounds.