High-throughput screening of 2D van der Waals crystals with plastic deformability

Abstract

Inorganic semiconductors exhibit multifarious physical properties, but they are prevailingly brittle, impeding their application in flexible and hetero-shaped electronics. The exceptional plasticity discovered in InSe crystal indicates the existence of abundant plastically deformable two-dimensional van der Waals (2D vdW) materials, but the conventional trial-and-error method is too time-consuming and costly. Here we report on the discovery of tens of potential 2D chalcogenide crystals with plastic deformability using a nearly automated and efficient high-throughput screening methodology. Seven candidates e.g., famous MoS2, GaSe, and SnSe2 2D materials are carefully verified to show largely anisotropic plastic deformations, which are contributed by both interlayer and cross-layer slips involving continuous breaking and reconstruction of chemical interactions. The plasticity becomes a new facet of 2D materials for deformable or flexible electronics.

High-Throughput Screening of Deformable Inorganic Layered Semiconductors

“…High-throughput screening is an efficient way to search for candidate materials with target properties. It has been successfully applied in the discovery of materials with excellent mechanical properties, such as exfoliable two-dimensional (2D) materials, ultrahigh-modulus crystals, plastic van der Waals (vdW) crystals, and so on. Therefore, the high-throughput screening method provides new opportunities to explore more deformable inorganic semiconductors, but it still needs to be developed.…”

“…With this deformability factor, the origin of room-temperature superdeformability of Ag 2 S and InSe was explained, and several brittle and deformable materials were verified . Moreover, it was further modified for high-throughput calculations for plastic deformability of 2D van der Waals crystals . However, since the cleavage energies and slipping energies in the deformability factor are hard to obtain quickly and require DFT calculations, the deformability factor needs to be further developed and simplified for the high-throughput screening of deformable inorganic semiconductors with high efficiency and low cost.…”

Dynamic Phase Transition Leading to Extraordinary Plastic Deformability of Thermoelectric SnSe2 Single Crystal

“…[9] Among the state-of-the-art plastic thermoelectric systems, the most groundbreaking and promising one is the discovery of inorganic semiconductors that are plastic/ductile at room temperature, [10] such as Ag 2 S [11] and its alloys, [12] and a class of binary two-dimensional van der Waals (2D vdW) chalcogenide crystals screened by high-throughput calculations. [13] However, the extraordinarily large plasticity of 2D vdW materials has only been observable in single-crystals, and their polycrystalline cousins completely [14] lose the plasticity and are as brittle as conventional thermoelectric materials. Despite the interlayer gliding and cross-layer dislocation slip in a deformed InSe crystal were observed by transmission electron microscopy (TEM), [15] these results did not disclose the innate brittle nature of the polycrystalline sample.…”

Plastically Deformable Inorganic Semiconductors

“…Enlightened by the features of InSe, the combination of a high cleavage energy, a low slip barrier, and a small in-plane modulus is proposed as the criterion for predicting new plastically deformable 2D vdW materials. This helps filter several potentially plastic materials such as SnSe 2 , [26] CrCl 3 , [17] CrI 3 , [17] GaSe, [6,18,27] PbI 2 , [28] and CuInP 2 S 6 . [28] Very recently, considering both the interlayer and cross-layer slip and cleavage processes, Gao et al developed a high-throughput screening methodology and discovered more plastically deformable vdW crystals such as MoS 2 , GaSe, and SnSe 2 .…”

“…[28] Very recently, considering both the interlayer and cross-layer slip and cleavage processes, Gao et al developed a high-throughput screening methodology and discovered more plastically deformable vdW crystals such as MoS 2 , GaSe, and SnSe 2 . [18] The plasticity thus adds a new facet to the famous 2D material alongside its marvelous physical properties. Further by Br doping, SnSe 2 crystals exhibit a high power factor of 10.8 μWcm -1 K -2 , which can be used as deformable or flexible TEG with high power density.…”