Modulation of electronic properties of MoS₂ nanoflakes: geometrical shapes and vacancy doping

After the exfoliation of single-layer graphene, many attempts to make devices using low-dimensional materials have been made. Due to the intrinsically thin body of the materials, conventional substitution doping is no longer available. Instead of substitution doping, we present atomic vacancy doping. In this talk, we show size-dependent characteristics and effects of sulfur atom vacancies of monolayer MoS₂ nanoflakes via numerical simulation. We study several types of flakes within the six-band tight-binding model. Vacancy position and concentration change the density of states of the system. Also, geometric shapes and the number of sites can affect electronic properties. By comparing the size and vacancy concentration of nanoflakes, we explain the correlation between in-gap states and vacancy rates. Since the density of states governs the charge transport, our results would give ideas for developing low-dimensional material-based devices.