Molecularly-thin anatase field-effect transistors fabricated through the solid state transformation of titania nanosheets

作者：Sekizaki S; Osadab M; Nagashio K^*

来源：Nanoscale, 2017, 9(19): 6471-6477.

DOI：10.1039/c7nr01305a

We demonstrate the field-effect transistor (FET) operation of a molecularly-thin anatase phase produced through solid state transformation from Ti0.87O2 nanosheets. A monolayer Ti0.87O2 nanosheet with a thickness of 0.7 nm is a two-dimensional oxide insulator in which Ti vacancies are incorporated, rather than oxygen vacancies. Since the fabrication method, in general, largely affects the film quality, the anatase films derived from the Ti0.87O2 nanosheets show interesting characteristics, such as no photocurrent peak at similar to 2 eV, which is related to oxygen vacancies, and a larger band gap of 3.8 eV. The 10 nm thick anatase FETs exhibit superior transport characteristics with a maximum mobility of similar to 1.3 cm(2) V-1 s(-1) and a current on/off ratio of similar to 10(5) at room temperature. The molecularly-thin anatase FET may provide new functionalities, such as field-effect control of catalytic properties.

• 出版日期2017-5-21