Distinct photoluminescence in multilayered van der Waals heterostructures of MoS2/WS2/ReS2 and BN

Van der Waals heterostructures of (TMDL=1/BNL=1-4/TMDL=1/BNL=1-4), [TMD = MoS2, WS2, and ReS2] are grown on c-plane sapphire substrate by pulsed laser deposition under slow kinetic condition. The heterostructure systems show strong emission around 2.3 eV and subsidiary peaks around 2.8, 1.9, 1.7 and 1.5 eV. BN and TMDs forms type-I heterojunction and the emission peaks observed are explained in terms of various band to band recombination processes and considering relative orientation of Brillouin Zones. The emission peak around 2.3eV is promising for solar and photovoltaic application. The observation is almost similar for three different heterostructure systems.