Graphdiyne@MoS2/WS2 heterostructures for infrared and visible photodetectors: A first-principles study

[Display omitted] •Bidirectional heterostructures based on graphdiyne and lateral heterostructures MoS2/WS2 are discussed.•G@MoS2/WS2 has a direct band gap and can be used for optoelectronic devices in the infrared regime.•G@MoS2/WS2 will transform from type-I to type-II and from semiconductor to metal under perpendicular electric field of 0.2 V/ Å and 0.5 V/ Å, respectively. MoS2/WS2 heterostructures are widely used in photonic and optoelectronic devices due to their excellent electronic properties and high chemical stability. Herein, we systematically investigated the graphdiyne@MoS2/WS2 heterojunction which demonstrates enhanced performance in the short-wavelength infrared regime. The bidirectional heterostructures have a much smaller bandgap (0.495 eV) compared to MoS2/WS2 (1.71 eV), which will extend the light absorption wavelengths. Further, the perpendicular electric field can effectively tune the band alignment of the bidirectional heterostructures. The critical electric fields, at which the transformation from type-I to type-II and semiconductor-to-metal transition occur, are calculated to be 0.2 V/Å and 0.5 V/Å, respectively. Our results show that the bidirectional heterostructures graphdiyne@MoS2/WS2 could be applied in the field of infrared photonics and optoelectronics.