Liquid Phase Exfoliated 2-D MoS2-Based Broadband Heterojunction Low-Powered Photosensor

Abstract

Researchers are facing a strong reverse thrust toward the exfoliation of 2-D materials at a large scale. These limitations restrict so many intensively needed applications. We have demonstrated chemically exfoliated MoS2 nanosheets-assisted photosensor examined for low-incident optical power ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.78 ~\mu \text{W}$ </tex-math></inline-formula> ) and bias voltage −0.5 to +0.5 V.X-ray diffraction (XRD) results show no secondary peaks that neglect the presence of any impurity in the synthesized MoS2. The high-resolution scanning electron microscopy (HR-SEM) shows synthesized flower-like MoS2 nanosheets. Exfoliation of MoS2 nanosheets was carried out in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${N}$ </tex-math></inline-formula> , <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${N}$ </tex-math></inline-formula> -methyl di-pyridine (NMP), a suitable solvent to develop single to few-layer MoS2 nanoflakes. During probe sonication, a low-temperature outer atmosphere arrangement has been ensured by using an ice bath. Sonicated solution has been centrifuged at 12 000 rpm, and the supernatant was collected and drop cast over a p-type (1,0,0) rectangular silicon wafer. Ohmic aluminum (Al) contact has been established. Current and voltage characteristics were performed to study the electrical behavior of fabricated p-Si and synthesized MoS2 heterostructure. The rectification ratio was ≈5800 achieved at ±2 V and the ideality factor was obtained 2.06 in the best-fitted region. The maximum responsivity and detectivity of 14.7 A/W and 2.25 jones were obtained at 300-nm wavelengths corresponding at low bias voltage of −0.5 V.