(333b) Temperature and Gate Dependent Photoresponse in MoS2-WS2 Heterostructures

Van der Waals heterostructures enable the combination of functionalities from different nanomaterials to achieve advanced, superimposed properties. Here, mixed MoS₂-WS₂ heterostructure grains were grown using atmospheric pressure chemical vapor deposition technique, and their optoelectronic properties were investigated. The field effect transistors fabricated from the heterostructure grains exhibited high photoresponsivity, which was influenced by the gating potential as well as the measurement temperature. During the gating potential sweep from -5 V to +55 V, the light to dark source drain current ratio (I_light/I_dark) decreased from 16 to 3 and from 7 to 2 at 60 K and 120 K, respectively. Such phenomena can be leveraged to realize novel optoelectronic and photovoltaic applications.