GeSe/MoS2 heterojunction diode for optoelectronic applications

Heterostructure engineering of two-dimensional (2D) layered materials offers an exciting opportunity to take advantage of each building block for fabricating new electronic and optical devices. The p-n junction diode constructed by heterostructures of 2D layered materials (e.g., MoS2/WSe2, MoS2/black phosphorus,) have been demonstrated to be excellent candidates for high-sensitive photodetectors with broad spectral response [1,2]. Recently, IV family monochalcogenides (e.g., GeS and GeSe) have been introduced as a new member of 2D material family and attracted much attention for the highly sensitive photodetector applications. The p-type semiconductor 2D GeSe has an orthorhombic structure with the band gap at around 1.1 eV. Accompanied by its strong light absorption property, the GeSe shows high-potential working as a photodetector with a broadband response from ultra-violate to near-infrared spectral regions [3]. By stacking n-type MoS2 and p-type GeSe, the formation of heterojunction diode is highly promising with unique optoelectronic properties.