Abstract
As a 2D material, MXene has emerged as an excellent electrode material for optoelectronic devices due to its high conductivity and hydrophilic surface. Here, the Ti 3 C 2 -based MXene was employed to construct the Ti 3 C 2 /ϵ-Ga 2 O 3 Schottky junction photodetector. The fabricated device demonstrated a self-powered operation manner with an extremely low dark current (0.07 pA), an outstanding light on/off switch ratio (2.5×10 6 ), a remarkable photo-response speed (43 ms/145 ms), a responsivity (R) of 15.5 mA/W, an external quantum efficiency (EQE) of 7.5% and a detectivity (D*) of 2.15×10 11 Jones. Such excellent photodetection performance that is comparable or even higher than those of Ga 2 O 3 Schottky photodetectors previously reported are originated from the excellent conductivity of MXene, good crystallization of ϵ-Ga 2 O 3 , and their well-matched energy level. Additionally, our Schottky junction device is capable of sensing solar-blind UV region and exhibits excellent stability in the air environment. The perfect combination of 2D MXene and wide-bandgap ϵ-Ga 2 O 3 proposes a novel route for the self-powered Schottky devices.