Controllable Synthesis of Crystalline ReS2(1-x)Se2x Monolayers on Amorphous SiO2/Si Substrates with Fast Photoresponse
Controllable Synthesis of Crystalline ReS2(1-x)Se2x Monolayers on Amorphous SiO2/Si Substrates with Fast Photoresponse
复制标题
在非晶 SiO2/Si 基底上可控合成具有快速光响应的晶体 ReS2(1-x)Se2x 单分子层
DOI：
10.1002/adom.201901415
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发表时间：
2019-12-20
影响因子：
9
通讯作者：
Xiao, Shaoqing
中科院分区：
文献类型：
--
作者：
Kang, Peipei;Nan, Haiyan;Xiao, Shaoqing
稀土过渡金属二卤化物(TMD)及其合金具有平面内各向异性的光学、电学和声子等特性，因而受到越来越多的研究兴趣。然而，扭曲的1T结构和较弱的层间耦合容易导致各向异性生长和面外生长，这使得在非晶态SiO_2/Si衬底上制备Re基TMD和合金单分子膜尤其具有挑战性。本文介绍了一种在SiO_2/Si衬底上用氯化钠辅助的受限空间化学气相沉积方法制备高质量大尺寸ReS_2(1-x)Se2x单层晶体的可靠方法。盐辅助和受限反应空间的协同作用促进了中间金属氧氯化物的形成，并创造了相对稳定的生长环境，最终在SiO_2/Si衬底上成功地合成了ReS_2(1-x)Se2x单层晶体。生长的ReS_2(1-x)Se_2x单层合金具有成分连续变化、晶体质量高、Re、S和Se元素分布均匀等特点。此外，基于ReS2(1-x)Se2x的光电探测器对可见光和近红外光表现出良好的光响应，其快速响应小于15ms。盐辅助受限空间化学气相沉积为在非晶态SiO_2/Si衬底上制备大规模低晶格对称性2D材料提供了可靠的途径，并为稀土基TMD及其合金在光电子器件中的应用开辟了新的前景。
Re-based transition metal dichalcogenides (TMDs) and alloys have many unusual features such as in-plane anisotropic optical, electrical, and phonon properties and thus receive increasing research interest. However, the distorted 1T structure and the weaker interlayer coupling easily cause anisotropic growth and out-of-plane growth, making it particularly challenging to produce Re-based TMD and alloy monolayers on amorphous SiO2/Si substrates. Here, a reliable method is developed for the synthesis of high-quality and large-size ReS2(1-x)Se2x monolayer crystals on SiO2/Si substrates by NaCl-assisted, confined-space chemical vapor deposition. The synergy of salt assistance with the confined reaction space facilitates the formation of intermediate metal oxychlorides and creates a relatively stable growth environment, finally leading to the successful synthesis of ReS2(1-x)Se2x monolayer crystals on SiO2/Si substrates. The as-grown ReS2(1-x)Se2x monolayer alloys exhibit continuously variable composition, high crystal quality, and uniform distribution of Re, S, and Se elements. Furthermore, the ReS2(1-x)Se2x based photodetectors display good photoresponse to visible and near-infrared light with a fast response of less than 15 ms. The salt-assisted, confined-space chemical vapor deposition provides a reliable way for the synthesis of large-scale low-lattice symmetry 2D materials on amorphous SiO2/Si substrates and opens up new prospects for Re-based TMDs and alloys in optoelectronic devices.