School of Materials Science and Engineering, Beihang University, Beijing 100191, P.R. China.
Nanoscale. 2017 Aug 3;9(30):10733-10740. doi: 10.1039/c7nr03445h.
Vertically stacked van der Waals (vdW) heterojunctions based on two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted a great deal of attention and have created a powerful new material platform for novel, high-performance electronic and optoelectronic devices. Here, we report the construction of multilayer p-MoTe/n-MoS vdW heterostructures with remarkable rectification behavior, self-powered photoresponse and distinct photosensitivity at different laser wavelengths and power densities. Field effect transistors (FETs) fabricated by MoTe/MoS heterojunctions exhibit excellent gate-tunable rectification behavior and p-n junction transport characteristics, with the n-type dominating. The MoTe/MoS heterojunction devices generate a self-powered photocurrent at zero bias voltage with a considerable on-off ratio reaching ∼780 and achieve a stable and fast photoresponse, due to the type-II band alignment facilitating efficient electron-hole separation. Utilizing the advantages of a p-n junction with type-II band alignment, this MoTe/MoS vdW heterostructure provides more opportunities for future electronic and optoelectronic applications.
基于二维（2D）过渡金属二卤化物（TMD）的垂直堆叠范德华（vdW）异质结引起了广泛关注，并为新型高性能电子和光电子器件创造了强大的新材料平台。在这里，我们报告了具有显著整流行为、自供电光响应和不同激光波长和功率密度下不同灵敏度的多层 p-MoTe/n-MoS vdW 异质结构的构建。通过 MoTe/MoS 异质结制造的场效应晶体管（FET）表现出优异的栅极可调整流行为和 p-n 结传输特性，其中 n 型占主导地位。MoTe/MoS 异质结器件在零偏压下产生自供电光电流，具有相当大的开/关比达到约 780，并实现了稳定快速的光响应，这归因于有利于有效电子-空穴分离的 II 型能带排列。利用具有 II 型能带排列的 p-n 结的优势，这种 MoTe/MoS vdW 异质结构为未来的电子和光电子应用提供了更多机会。
