Tuning the Electronic and Photoelectronic Properties of Two-Dimensional MoSe2Thin Films by In Situ V-Doping

Atom-substituting doping by atmospheric-pressure chemical vapor deposition (AP-CVD) is an effective and promising strategy for changing the properties of two-dimensional transition-metal dichalcogenides (2D TMDs). In this paper, we successfully grew V-doped MoSe2films. The photoluminescence (PL) spectra gradually red-shifted with the increase of the doping concentration, the X-ray photoelectron spectroscopy (XPS) after doping shifted toward a lower binding energy, and the change of polarity before and after doping can be seen in the transfer characteristic curves of back-gated field-effect transistors (FETs) based on V-doped and undoped MoSe2films and proves that the V atom successfully replaces the Mo atom and acts as a p-type dopant, which greatly improves the properties of back-gated FETs based on 2D V-doped MoSe2. The hole mobility of the doped samples can reach 111.34 cm2V–1s–1, the Ion/Ioffratio of the hole branch can reach 107, and the detector has a fast response time of 2.3 ms. The results show that the band gap, polarity, optical properties, and electrical properties of 2D MoSe2can be effectively adjusted by changing the V concentration, which provide a feasible way for 2D materials to realize high-performance scalable microelectronic devices and also provide new opportunities for 2D materials in electronic or optoelectronic applications.