Theoretical design and discovery of two‐dimensional materials for next‐generation flexible piezotronics and energy conversion

Abstract Two‐dimensional (2D) materials are at the epicenter of the current nanotechnology research for its intriguing properties. It has the advantage of high flexibility, high surface to volume ratio, robust mechanical strength and are stackable in contrary to bulk materials. Piezoelectric effect is exploited in 2D layered nanomaterials with broken inversion symmetry and non‐zero band gap for applications in energy harvesting and energy conversion. Density functional theory (DFT) is a powerful tool to predict the piezoelectric properties of 2D materials. This mini review emphasizes the importance and discusses the challenges of different methods within DFT‐based framework to compute piezoelectric properties. Recent simulation works of piezoelectric engineering in novel 2D semiconductors for in‐plane and out‐of‐plane piezoelectricity are reviewed. Various controlling parameters and techniques for piezoelectric effect are also discussed. Theoretical predictions pave the path for experimental exploration of 2D materials exhibiting strong piezoelectric properties and to replace the commercially used lead‐based toxic materials in future devices.