Experimental and theoretical demonstrations of ultraviolet absorption enhancement in porous nano-membrane graphene

Ultraviolet absorbing materials have important applications in which graphene is a strong candidate, yet, few efforts are being exerted to improve its absorption in the UV-region. We show that UV absorption in single-layer graphene can be enhanced by manoeuvring its electronic properties through converting it to a nanomembrane-like structure, or nanomesh. Regular and irregular pores were created by Electron Beam Lithography and a lithography-free process respectively. Theoretical calculations, using density functional theory, confirmed the experimental results, and indicated that the absorption peaks are a result of changes in the band structures of the nanomembrane graphene (NMGs) arising from the pore superlattice.