Kim Doyeon, Park Kidong, Lee Jong Hyun, Kwon Ik Seon, Kwak In Hye, Park Jeunghee
Department of Advanced Materials Chemistry, Korea University, Sejong, 339-700, Republic of Korea.
Small. 2021 Mar;17(10):e2006310. doi: 10.1002/smll.202006310. Epub 2021 Feb 16.
Recently, extensive efforts have been directed at finding novel 2D-layered structures with anisotropic crystal structures. Herein, the in-plane anisotropic optical and (photo)electrical properties of 2D SiAs nanosheets synthesized using a solid-state reaction and subsequent mechanical exfoliation are reported. The angle-resolved polarized Raman spectrum shows high in-plane anisotropy of the phonon vibration modes, which are consistent with the theoretical prediction. Field-effect transistor devices fabricated using the SiAs nanosheets demonstrate significant anisotropy in the hole mobility with an anisotropic ratio as high as 5.5. Photodetectors fabricated with single SiAs nanosheet exhibit high sensitivity in the UV-visible region, and the anisotropic ratio of the photocurrent reaches 5.3 at 514.5 nm and 2.3 at 325 nm. This work lays the foundation for future research in anisotropic 2D materials.
最近，人们致力于寻找具有各向异性晶体结构的新型二维层状结构。在此，报道了通过固态反应和随后的机械剥离合成的二维SiAs纳米片的面内各向异性光学和（光）电性质。角分辨偏振拉曼光谱显示出声子振动模式的高面内各向异性，这与理论预测一致。使用SiAs纳米片制造的场效应晶体管器件在空穴迁移率方面表现出显著的各向异性，各向异性比高达5.5。用单个SiAs纳米片制造的光电探测器在紫外-可见光区域表现出高灵敏度，在514.5 nm处光电流的各向异性比达到5.3，在325 nm处达到2.3。这项工作为未来各向异性二维材料的研究奠定了基础。
