High-performance MoSe2 homojunction infrared photodetector

Two-dimensional (2D) materials with unique structural and physical properties are urgent to exploit and may be applied in the next-generation electronics and infrared detectors. The homojunction devices are ideal and promising candidates compared to heterojunction devices since there are no interface problems, such as unintentionally induced impurities and charge-trapped sites. In this work, we reported a high-performance MoSe2 homojunction infrared photodetector. MoSe2 homojunction devices directly consist of thick and thin MoSe2. MoSe2 homojunction diodes exhibit different rectified characteristics including forward and reverse rectifications, which are dependent on the back-gate voltage. Remarkably, MoSe2 homojunction photodetectors possess a broadband photoresponse with the wavelength from visible to near-infrared at room temperature. The responsivity of MoSe2 homojunction photodetectors under 940 nm laser illumination is approximately 2.25 A W-1. Additionally, the obtained specific detectivity of MoSe2 homojunction device is over 10(10) Jones. Our findings provide an excellent way to fabricate feasible homojunction devices. Meanwhile, homojunction devices also show the wealthy potential in novel electronic and optoelectronic devices.