Unusual mechanical and electronic behaviors of bulk layered hydrogen substituted graphdiyne under biaxial strain

Abstract

Recently, a novel layered carbon-based material, i.e. the hydrogen substituted graphdiyne (HsGDY), has been synthesized through an in situ cross-coupling reaction of triethynylbenzene (Nat. Commun., 2017, 8, 1172). Herein, the most favorable stacking order for bulk layered HsGDY (b-HsGDY) was determined based on first-principles calculations, and then its mechanical and electronic properties under biaxial strain were systematically studied. The results show that the ABC-stacking structure is the most favorable configuration for b-HsGDY. Interestingly, this material exhibits a behavior similar to an auxetic material under biaxial tensile strain and its band gap increases with the increase of either the tensile strain or the compression strain within the strain range of -0.03≤ε≤0.05. These extraordinary properties endow the b-HsGDY with great potential in designing electromechanical devices.