An effective strategy to search for 2D piezoelectric materials

Two-dimensional (2D) piezoelectric materials have a great potential for device applications by utilizing their remarkable electromechanical coupling. In this study, we propose a sure independence screening and sparsifying operator algorithm to search for 2D piezoelectric materials, which is culminating in the identification of a novel 2H-MoS2-like crystalline structure. Utilizing first-principles calculations grounded in density-functional theory, we systematically conducted a thorough analysis of their mechanical properties, electronic properties, and piezoelectric responses. The results indicate that 2H-MoS2-like crystalline structures exhibit the most superior piezoelectric characteristics and have an e11 coefficient of up to 5.09 and a d11 coefficient reaching 10.87, showing remarkable piezoelectric performance. Employing Kendall correlation analysis and polynomial regression, we analyzed the relations between physical parameters and piezoelectric properties, yielding empirical equation that encapsulate the piezoelectric nature of this new class of materials, which mostly related to their lattice structures and bandgaps. Then, we investigated the stress, system energy, and piezoelectric response of these materials under various strain conditions, a d11 coefficient reaching 12.07 for WMo3Se8. Our work may broaden the horizon of low-dimensional piezoelectric materials, offering a pathway to tailor materials with desired properties through our proposed effective strategy.