Sizable bandgaps of graphene in 3d transition metal intercalated defective graphene/WSe 2 heterostructures

• Published in: RSC advances 2019-06, Vol.9 (32), p.18157-18164
• Main Authors: Zhang, Xiuyun, Sun, Yi, Gao, Weicheng, Lin, Yin, Zhao, Xinli, Wang, Qiang, Yao, Xiaojing, He, Maoshuai, Ye, Xiaoshan, Liu, Yongjun
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c9ra03034d

Controlling the electronic and magnetic properties of G/TMD (graphene on transition metal dichalcogenide) heterostructures is essential to develop electronic devices. Despite extensive studies in perfecting G/TMDs, most products have various defects due to the limitations of the fabrication techniques, and research investigating the performances of defective G/TMDs is scarce. Here, we conduct a comprehensive study of the effects of 3d transition metal (TM = Sc-Ni) atom-intercalated G/WSe heterostructures, as well as their defective configurations having single vacancies on graphene or WSe sublayers. Interestingly, Ni-intercalated G/WSe exhibits a small band gap of 0.06 eV, a typical characteristic of nonmagnetic semiconductors. With the presence of one single vacancy in graphene, nonmagnetic (or ferromagnetic) semiconductors with sizable band gaps, 0.10-0.51 eV, can be achieved by intercalating Ti, Cr, Fe and Ni atoms into the heterostructures. Moreover, V and Mn doped non-defective and Sc, V, Co doped defective G/WSe can lead to sizable half metallic band gaps of 0.1-0.58 eV. Further analysis indicates that the significant electron transfer from TM atoms to graphene accounts for the opening of a large band gap. Our results provide theoretical guidance to future applications of G/TMD based heterostructures in (spin) electronic devices.