Facile synthesis of graphene quantum dots from 3D graphene and their application for Fe³⁺ sensing

Owing to their small size, biocompatibility, unique and tunable photoluminescence, and physicochemical properties, graphene quantum dots (GQDs) are an emerging class of zero-dimensional materials promising a wide spectrum of novel applications in bio-imaging, optical, and electrochemical sensors, energy devices, and so forth. Their widespread use, however, is largely limited by the current lack of high yield synthesis methods of high-quality GQDs. In this contribution, a facile method to electrochemically exfoliate GQDs from three-dimensional graphene grown by chemical vapor deposition (CVD) is reported. Furthermore, the use of such GQDs for sensitive and specific detection of ferric ions is demonstrated. A facile and high-yield synthesis method for high quality and strongly photoluminescent graphene quantum dots (GQDs) by electrochemically exfoliating free standing three dimensional graphene foam is demonstrated. The synthesized GQDs are utilized for specific optical detection of ferric ions.