Quantum Dot Modification of Large Area Graphene Surfaces via Amide Bonding

Abstract

Large‐area graphene grown by chemical vapor deposition is functionalized by p‐aminophenyl groups via the diazonium‐route. Subsequently, carboxylic acid‐modified CdSXSe1‐X/ZnS dots (QDs) with maximum emission wavelengths of 540 nm and 630 nm are immobilized via amidation reaction to the amino‐functionalized graphene on the copper growth substrate forming stable covalent bonds in all functionalization steps. After immobilization of the QDs, the functional QD/graphene stack is available for transfer from the growth substrate onto any other substrate. In this study, the QD‐modified graphene is transferred to a Si wafer with surface oxide without losing the QD modification. The successful binding of the QDs onto the functionalized graphene is characterized by their vibrational signature using Raman backscattering and infrared‐spectroscopic ellipsometry and by their specific light emission as measured by photoluminescence (PL) spectroscopy.