Ultrathin tellurium dioxide: emerging direct bandgap semiconductor with high-mobility transport anisotropyElectronic supplementary information (ESI) available. See DOI: 10.1039/c8nr01028e

• Main Authors: Guo, Shiying, Zhu, Zhen, Hu, Xuemin, Zhou, Wenhan, Song, Xiufeng, Zhang, Shengli, Zhang, Kan, Zeng, Haibo
• Format: Journal Article
• Language: English
• Published: 10.05.2018
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c8nr01028e

An effectively large bandgap and a high carrier mobility of two dimensional (2D) crystals are crucial in emerging materials for nanoelectronics. A previously unexplored two-dimensional material, monolayer TeO 2 , is proposed to have high stability, a wide direct gap and high carrier mobility, based on first-principles calculations. Our results show that 2D TeO 2 is both thermally and dynamically stable. In addition, it is easily exfoliated from its bulk counterpart, a natural layered mineral tellurite. Importantly, 2D TeO 2 always exhibits a direct bandgap when thinning from bulk (3.32 eV) to monolayer (3.70 eV), an energy range not covered by previously reported 2D materials. Furthermore, monolayer TeO 2 is exceptional in high transport anisotropy, possessing not only high electron mobility (of the order of 1000 cm 2 V −1 s −1 ) but also exceptionally high hole mobility (up to 9100 cm 2 V −1 s −1 ). All these findings make 2D TeO 2 a promising candidate for both power electronics and short-wavelength optoelectronic applications. Ultrathin TeO 2 exhibits a wide direct band-gap and high hole mobility for both power electronics and short-wavelength optoelectronic applications.