Computational design and property predictions for two-dimensional nanostructures

Recent success in isolating and growing various two-dimensional (2D) materials with intriguing properties has pushed forward the search for new 2D nanostructures with novel properties. Current experimental trial-and-error methods face the fundamental challenges of low efficiency and a lack of clear guidelines. In contrast, based on state-of-the-art first-principles calculations and well-developed structural prediction algorithms, computational simulations can not only predict an increasing number of new 2D materials with desirable properties but also suggest their possible synthesis routes. Among them, many predictions, such as the growth of monolayer boron sheets (borophene), piezoelectricity in molybdenum disulfide (MoS2), ferroelectricity in tin telluride (SnTe), topological defects in transition metal dichalcogenides, Dirac cones in borophene, and high carrier mobility and mobility anisotropy in black phosphorene, have been verified by experiments, showing the accuracy of computational approaches, as well as their power in facilitating experimental exploration in 2D flatland. To date, the rapid expansion in theoretical work has generated a large number of very important results, but the overall picture of recent progress, current challenges, and future opportunities is rarely discussed. Accordingly, this review aims at providing information about current trends and future perspectives for 2D materials research. To achieve this, the review is organized as follows: (1) discussion of structural predictions in 2D materials using borophene as an example; (2) predictions of the electronic, optical, mechanical, and magnetic properties in various 2D materials; (3) discussion of the influence of defects on the structures and properties of 2D materials; and (4) evaluation of current progress in computational simulations and perspectives for future development.