Defect Passivation and Photoluminescence Enhancement of Monolayer MoS2 Crystals through Sodium Halide-Assisted Chemical Vapor Deposition Growth.,ACS Applied Materials & Interfaces

当前位置： X-MOL 学术 › ACS Appl. Mater. Interfaces › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Defect Passivation and Photoluminescence Enhancement of Monolayer MoS2 Crystals through Sodium Halide-Assisted Chemical Vapor Deposition Growth.
ACS Applied Materials & Interfaces ( IF 8.3 ) Pub Date : 2020-02-02 , DOI: 10.1021/acsami.9b19224
Wenfeng Wang ₁ , Haibo Shu ₁ , Jun Wang ₁ , Yecheng Cheng ₁ , Pei Liang ₁ , Xiaoshuang Chen ₂

Affiliation

Recent success in the chemical vapor deposition (CVD) growth of atomically thin transition metal dichalcogenide (TMD) crystals opens up prospects for exploiting these materials in nanoelectronic and optoelectronic devices. However, CVD-grown TMDs often suffer from weak crystal quality because of the formation of defects during the growth, which makes a large impact on their electrical and optical properties. Here, we report a facile synthesis of high-quality MoS2 monolayers through a sodium halide-assisted CVD method. Our results show that the addition of sodium halides into MoO3 precursors leads to the rapid growth of highly crystalline MoS2 monolayers. Moreover, the overall photoluminescence (PL) intensity of MoS2 monolayers can be greatly enhanced by up to 2 orders of magnitude. The PL enhancement originates from that the deep trap states induced by sulfur vacancies are passivated by the substitution doping of halogen atoms, which promotes the emission of excitons and trions. Density functional theory calculations indicate that the band gaps of halogen-doped MoS2 monolayers are slightly smaller than those of pristine MoS2 monolayer, which is responsible for the small red shift of PL peaks (∼30 meV). These findings provide a new route toward engineering electronic and optical properties of MoS2 and other TMD monolayers.

中文翻译：

通过卤化钠辅助化学气相沉积生长的单层MoS2晶体的缺陷钝化和光致发光增强。

在原子上薄的过渡金属二卤化二硫（TMD）晶体的化学气相沉积（CVD）生长方面的最新成功为在纳米电子和光电子器件中开发这些材料打开了前景。然而，由于生长过程中形成缺陷，因此CVD生长的TMD经常遭受晶体质量较弱的影响，这对其电学和光学性能产生很大影响。在这里，我们报告了通过卤化钠辅助CVD方法轻松合成高质量的MoS2单层。我们的结果表明，将卤化钠添加到MoO3前体中会导致高度结晶的MoS2单层快速生长。此外，MoS2单层的整体光致发光（PL）强度可以大大提高2个数量级。PL增强的原因在于，由硫空位引起的深陷阱态被卤素原子的取代掺杂钝化，从而促进了激子和三子的发射。密度泛函理论计算表明，掺卤素的MoS2单层的带隙略小于原始的MoS2单层的带隙，这是PL峰的小红移（约30 meV）的原因。这些发现为MoS2和其他TMD单层的工程电子和光学性能提供了一条新途径。这是造成PL峰的小红移（约30 meV）的原因。这些发现为MoS2和其他TMD单层的工程电子和光学性能提供了一条新途径。这是造成PL峰的小红移（约30 meV）的原因。这些发现为MoS2和其他TMD单层的工程电子和光学性能提供了一条新途径。

更新日期：2020-02-13

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南