Defect assisted coupling of a MoS sub(2)/TiO sub(2) interface and tuning of its electronic structure

• Published in: Nanotechnology 2016-09, Vol.27 (35), p.355203-355210
• Main Authors: Chen, Guifeng, Song, Xiaolin, Guan, Lixiu, Chai, Jianwei, Zhang, Hui, Wang, Shijie, Pan, Jisheng, Tao, Junguang
• Format: Article
• Language: English
• Subjects: Atomic structure; Chemically bonded; Etching; Molybdenum disulfide; Nanostructure; Nanotechnology; Titanium dioxide; Tuning
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/0957-4484/27/35/355203

Although MoS sub(2) based heterostructures have drawn increased attention, the van der Waals forces within MoS sub(2) layers make it difficult for the layers to form strong chemical coupled interfaces with other materials. In this paper, we demonstrate the successful strong chemical attachment of MoS sub(2) on TiO sub(2) nanobelts after appropriate surface modifications. The etch-created dangling bonds on TiO sub(2) surfaces facilitate the formation of a steady chemically bonded MoS sub(2)/TiO sub(2) interface. With the aid of high resolution transmission electron microscope measurements, the in-plane structure registry of MoS sub(2)/TiO sub(2) is unveiled at the atomic scale, which shows that MoS sub(2)[1-10] grows along the direction of TiO sub(2)[001] and MoS sub(2)[110] parallel to TiO sub(2)[100] with every six units of MoS sub(2) superimposed on five units of TiO sub(2). Electronically, type II band alignments are realized for all surface treatments. Moreover, the band offsets are delicately correlated to the surface states, which plays a significant role in their photocatalytic performance.