Tunability of 2D Graphene/H-diamane heterostructure under external electric field and strain engineering

Heterostructures have various physical and chemical properties compared to single-layer two-dimensional materials (2DMs), providing an effective method for improving optoelectronic device's performance. ln this work, we systematically examined the electronic structures, contact types, and optical properties of the Graphene/H-diamane heterostructure (Gr/H-diamane HTS) made of Gr and 2D H-diamane by the first-principles method. This HTS displays a p-type Schottky contact with a Schottky barrier height (SBH) of 0.01 eV. The SBH can be effectively tuned by applying electric field (EF) and strain engineering, and the transition from Schottky contact to Ohmic contact can be realized under vertical strain or external EF, which contributes to the improvement of device performance. In addition, the Gr/H-diamane HTS has a work function difference of 0.61 eV and a strong absorption capacity for infrared, visible, and ultraviolet light. Its peak absorption coefficient in the infrared region reaches 4 × 10⁶ cm^-1 and can be improved even further under EF. Therefore, the Gr/H-diamane HTS has enormous potential in applications including high-performance nanoelectronics and infrared photodetectors.