School of Advanced Materials and Nanotechnology, Xidian University, Xi'an 710126, People's Republic of China.
Nanotechnology. 2017 Aug 11;28(32):325602. doi: 10.1088/1361-6528/aa6f01.
Transition metal dichalcogenides (TMDs) have attracted considerable interest for exploration of next-generation electronics and optoelectronics in recent years. Fabrication of in-plane lateral heterostructures between TMDs has opened up excellent opportunities for engineering two-dimensional materials. The creation of high quality heterostructures with a facile method is highly desirable but it still remains challenging. In this work, we demonstrate a one-step growth method for the construction of high-quality MoS-WS in-plane heterostructures. The synthesis was carried out using ambient pressure chemical vapor deposition (APCVD) with the assistance of sodium chloride (NaCl). It was found that the addition of NaCl played a key role in lowering the growth temperatures, in which the Na-containing precursors could be formed and condensed on the substrates to reduce the energy of the reaction. As a result, the growth regimes of MoS and WS are better matched, leading to the formation of in-plane heterostructures in a single step. The heterostructures were proved to be of high quality with a sharp and clear interface. This newly developed strategy with the assistance of NaCl is promising for synthesizing other TMDs and their heterostructures.
近年来，过渡金属二硫属化物（TMDs）因其在下一代电子学和光电子学方面的探索而引起了极大的关注。在 TMDs 之间制造平面横向异质结构为二维材料的工程设计开辟了极好的机会。用简单的方法制造高质量的异质结构是非常理想的，但仍然具有挑战性。在这项工作中，我们展示了一种一步生长法来构建高质量的 MoS-WS 平面异质结构。该合成是在环境压力化学气相沉积（APCVD）的帮助下，使用氯化钠（NaCl）进行的。研究发现，添加 NaCl 对降低生长温度起着关键作用，其中含 Na 的前体可以形成并在衬底上凝结，从而降低反应的能量。结果，MoS 和 WS 的生长区更好地匹配，导致在单个步骤中形成平面异质结构。证明异质结构具有高质量，界面清晰锐利。在 NaCl 的辅助下，这种新开发的策略有望用于合成其他 TMDs 及其异质结构。
