Electronic and optical properties of XN-ynes (X = B, Al, Ga): A first-principle study with many-body effects

Abstract

This study aims to engineer electronic and optical properties of newly designed ‘graphyne with XN at hexagonal ring’ (labeled as XN-ynes, where X = B, Al, Ga). Except BN-yne, all XN-ynes are indirect band gap semiconductors, having larger gap than pristine graphyne. The Raman and IR spectra of XN-yne exhibit quite distinct feature with respect to pristine graphyne and strong Raman and IR line shows regular dependence on group IIIA element, thus may help to detect them during synthesis. The optical band gap calculated by G0W0 and Bethe-Salpeter equation (BSE) approach indicates the possibility of their usage as UV light absorber. The optical band gap is arises from π to π* transition. Not only optical band gap but also the strong absorption peak lies in UV region of electromagnetic spectra that also suggesting their possible use as UV light absorber. This study proposes an important initial step towards the applications of these newly designed XN-ynes.