Modulation of optical and electrical characteristics by laterally stretching DNAs on CVD-grown monolayers of MoS2

Abstract

Monolayer MoS2 (1L-MoS2) is an ideal platform to examine and manipulate two dimensionally confined exciton complexes, which provides a large variety of modulating the optical and electrical properties of 1L-MoS2. Extensive studies of external doping and hybridization exhibit the possibilities of engineering the optical and electrical performance of 1L-MoS2. However, biomodifications of 1L-MoS2 and the characterization and applications of such hybrid structures are rarely reported. In this paper, we present a bio-MoS2 hybrid structure fabricated by laterally stretching strands of DNAs on CVD-grown 1L-MoS2. We observed a strong modification of photoluminescence and Raman spectra with reduced PL intensity and red-shift of PL peak and Raman peaks, which were attributed to electron doping by the DNAs and the presence of tensile strain in 1L-MoS2. Moreover, we observed a significant enhancement of electric mobility in the DNA/1L-MoS2 hybrid compared to that in the pristine 1L-MoS2, which may have been caused by the induced strain in 1L-MoS2.