†Center for Artificial Low-Dimensional Electronic Systems, Institute for Basic Science (IBS), ‡Division of Advanced Materials Science, and §Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Pohang 790-784, Korea.
Nano Lett. 2015 Jun 10;15(6):3703-8. doi: 10.1021/acs.nanolett.5b00079. Epub 2015 May 6.
van der Waals layered materials have large crystal anisotropy and crystallize spontaneously into two-dimensional (2D) morphologies. Two-dimensional materials with hexagonal lattices are emerging 2D confined electronic systems at the limit of one or three atom thickness. Often these 2D lattices also form orthorhombic symmetries, but these materials have not been extensively investigated, mainly due to thermodynamic instability during crystal growth. Here, we show controlled polymorphic growth of 2D tin-sulfide crystals of either hexagonal SnS2 or orthorhombic SnS. Addition of H2 during the growth reaction enables selective determination of either n-type SnS2 or p-type SnS 2D crystal of dissimilar energy band gap of 2.77 eV (SnS2) or 1.26 eV (SnS) as a final product. Based on this synthetic 2D polymorphism of p-n crystals, we also demonstrate p-n heterojunctions for rectifiers and photovoltaic cells, and complementary inverters.
范德华层状材料具有较大的晶体各向异性，会自发结晶成二维（2D）形态。具有六方晶格的二维材料是在一个或三个原子厚度极限处出现的二维受限电子系统。这些二维晶格通常也形成正交对称，但这些材料尚未得到广泛研究，主要是由于晶体生长过程中的热力学不稳定性。在这里，我们展示了 2D 锡-硫族化物晶体的控制多晶型生长，包括六方 SnS2 或正交 SnS。在生长反应中添加 H2 可以选择性地确定 n 型 SnS2 或 p 型 SnS 2D 晶体，其最终产物的能带隙分别为 2.77eV（SnS2）或 1.26eV（SnS）。基于这种合成的 p-n 晶体的二维多晶型性，我们还展示了用于整流器和光伏电池以及互补逆变器的 p-n 异质结。
