MoS2 and other layered transition metal dichalcogenides (TMDs) have been the subject of intense investigation because single and few-layered MoS2 exhibits novel properties that are distinctly different from those of graphene. Whereas graphene is a gapless materials, the stable 2H form of single layered MoS2 is a direct band gap semiconductor. In addition, single and few-layered MoS2 has relatively high carrier mobility, large current on/off ratio and strong coupling of spin and valley degrees. Recently, single or few layer MoS2 nanoeletronic and optoelectronic have been studied because of it's optical activity. But, until now, previous reports related to the optical properties of large area and high quality MoS2 are limited. In this work, we report the growth of large scale two-dimensional and high crystal quality MoS2 on the sapphire substrate by low-pressure chemical vapor deposition and its properties as photodetectors.