Impact of Type and Degree of Defect on Selected Properties of Graphene Quantum Dots

Graphene quantum dots (QGDs), as nascent carbon-based materials, demonstrate remarkable promise in many different applications. Thanks to excellent electrical and thermal properties, great biocompatibility, feasibility of surface functionalization and low cytotoxicity, QGDs can be any material and have many applications, from elastic PV panels to drug delivery. This paper concentrates on relating the structure of the QGD (which is the result of the synthesis method used and consequently the variable degree of defect, the possible presence of functional groups especially in the defect region, etc.) to the resulting physicochemical properties. Therefore, the aim of this study is to theoretically relate and determine the effect of defect amount and type on the value of the HOMO–LUMO gap with respect to possible QGD luminescence colors. Finally, it presents a direction in new graphene-based materials synthesis, where every single defect has a huge impact on its properties.