Photoluminescence study of optically active diaminopyridine intercalated graphene oxide

Diaminopyridine (DAP) ligand is successfully intercalated in GO layers to achieve a layered-type structure with interlayer separation similar to 1.03 nm. Density functional theory (DFT) was applied to investigate the stability of the modified structure along with its interlayer separation, and agrees well with the experimental results. As-synthesized diaminopyridine functionalized GO (DAP-fGO) composites show better photoluminescent (PL) property compared with GO via surface passivation. Experimental observation of excitation-dependent PL spectra of DAP-fGO composite was further verified by DFT calculations of HOMO-LUMO band gaps. We believe that this study will help to design different GO-based nanomaterials with potential physical, chemical and optical applications.