Abstract

Functionalization of the surface of biosensors with biomaterials such as proteins and DNA has been widely employed to establish a specific selectivity and high sensitivity to target molecules. As for sensing materials, a group of transition metal dichalcogenides (TMDC), e.g., MoS₂ and WS₂, has attracted much attention due to their superior optoelectronic properties as well as its atomically flat surface. Single-layer MoS₂ has shown strong photoluminescence (PL) under photoexcitation, and the PL is largely affected by surrounding environments, such as molecular adsorption and solvent [1,2]. Thus, MoS₂ can be a good candidate for an optical biosensor under physiological condition due to its high sensitivity to the environments. To this end, it is necessary to investigate the optical response of MoS₂ to various aqueous conditions of pH and ions. However, despite of intensive studies, the MoS₂ PL under aqueous solution is poorly investigated.

© 2017 Japan Society of Applied Physics, Optical Society of America