Ti<sub>3</sub>C<sub>2</sub>/ϵ-Ga<sub>2</sub>O<sub>3</sub>Schottky Self-Powered Solar-Blind Photodetector With Robust Responsivity
Zuyong Yan, Shan Li, Zeng Liu, Wenjie Liu, Fen Qiao, Peigang Li, Xiao Tang, Xiaohang Li, Jianying Yue, Yufeng Guo, Weihua Tang
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 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -based MXene was employed to construct the Ti <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /ϵ-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> 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 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> ), 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 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sup> Jones. Such excellent photodetection performance that is comparable or even higher than those of Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Schottky photodetectors previously reported are originated from the excellent conductivity of MXene, good crystallization of ϵ-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> , 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 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> proposes a novel route for the self-powered Schottky devices.