All-Solution Fabricated MXene/GaAs Self-Driven Photodetector with an Inserted Graphene Oxide Interface Layer

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• MXene is a novel 2D material with unique photoelectric properties.
• Van der Waals Schottky heterojunctions are promising for photodetector fabrication.
• Schottky interfacial states can degrade device performance.

Purpose of the Study:

• To develop a Ti₃C₂T/GO/GaAs van der Waals Schottky junction photodetector.
• To mitigate performance deterioration using an interface engineering technique.
• To achieve high detectivity and fast response in a self-driven photodetector.

Main Methods:

• Fabrication of a Ti₃C₂T/GO/GaAs heterojunction using an all-solution method.
• Incorporation of a graphene oxide (GO) interfacial barrier layer.
• Characterization of the photodetector's performance, including dark current, detectivity, and response speed.

Main Results:

• The GO interfacial layer effectively reduced dark-current noise, resulting in ultralow dark current at zero bias.
• Achieved a high specific detectivity of 1.4 × 10¹³ Jones and ultrafast response times (41.7/40.0 μs).
• Demonstrated a broad-band response from 405 to 980 nm, with infrared response attributed to MXene's plasmon effect.

Conclusions:

• The Ti₃C₂T/GO/GaAs photodetector offers a simple fabrication process and high performance.
• The device is suitable for monitoring weak light signals due to its high specific detectivity.
• This self-driven photodetector serves as a foundation for various light detection applications.