G0W0 Calculations of optoelectronic properties of Graphene/hBN for Solar cells and near infrared Photodetector.

It is known that low optical absorption in graphene-based devices can be dramatically improved. However, integrating hexagonal boron nitride (hBN) with graphene in a heterostructure appears to be a promising approach to open the band gap in graphene in order to overcome the low absorption behavior in graphene-based devise for optoelectronic applications. Hence, to expose the hidden potential of hBN heterostructure, detailed knowledge of its electronic properties are needed. In this paper, electronic properties of hBN/graphene heterostructure are performing by highly accurate first-principles many-body perturbation theory. The calculated G0W0 band gap of hBN sheet was found to be 6.09 eV and this value is in good agreement with experimental value of 6 eV. For the heterostructure the calculated band gaps of hBN/graphene by varying the interlayer distance from 1.5 to 3.5 Å was found to be 1.76, 1.70, 0.84, 0.22 0.04 eV for interlayer distance of 1.5, 2.0, 2.5, 3.0 and 3.5 eV. The energy analysis of hBN/graphene heterostructure reveals that the most stable configuration is the one in which the either B or N atom of hBN facing to graphene is above the hole center of graphene. More attractively, strong absorption within visible light wavelengths in hBN/graphene sheets suggest that the heterostructure is a promising candidate for solar cells applications.