Graphene-MoS2 hybrid nanostructures enhanced surface plasmon resonance biosensors
Date of Issue2014
School of Electrical and Electronic Engineering
Research Techno Plaza
In this work, we propose a new configuration of surface plasmon resonance (SPR) sensor that is based on graphene–MoS2 hybrid structures for ultrasensitive detection of molecules. The proposed system displays a phase-sensitivity enhancement factor of more than 500-fold when compared to the SPR sensing scheme without the graphene–MoS2 coating or with only graphene coating. Our hypothesis is that the monolayer MoS2 has a much higher optical absorption efficiency (∼5%) than that of the graphene layer (∼2.3%). Based on our findings, the electron energy loss of MoS2 layer is comparable to that of graphene and this will allow a successful (∼100%) of light energy transfer to the graphene–MoS2 coated sensing substrate. Such process will lead to a significant enhancement of SPR signals. Our simulation shows that a quasi-dark point of the reflected light can be achieved under this condition and this has resulted in a steep phase jump at the resonance angle of our newly proposed SPR system. More importantly, we found that phase interrogation detection approach of the graphene–MoS2 hybrid structures-based sensing system is more sensitive than that of using the regularly angular interrogation method and our theoretical analysis indicates that 45 nm of Au film thickness and 3 coating layers of MoS2 nanosheet are the optimized parameters needed for the proposed SPR system to achieve the highest detection sensitivity range.
DRNTU::Engineering::Electrical and electronic engineering::Electronic systems::Biometrics
Sensors and Actuators B : chemical
© 2014 Elsevier B.V. This is the author created version of a work that has been peer reviewed and accepted for publication by Sensors and Actuators B: Chemical, Elsevier B.V.. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1016/j.snb.2014.10.124].