Recent advances in the graphene quantum dot-based biological and environmental sensors

Abstract

Graphene quantum dots (GQDs) are zero-dimensional (0D) materials having unique luminescence properties due to quantum confinement and edge effect. Coupled with their large surface area, chemical- and photostabilities, biocompatibility, and low-toxicity, GQDs have enchanted many attentions for fundamental research and applications. In particular, the broad synthesis methods with ease of functionalization and controlled-synthesis as well as large variety of naturally available precursors, have made GQDs to be suitable for the development of advanced, rapid, and versatile optical-based biological and environmental sensors with high sensitivity and selectivity. In this review, we summarize the intrinsic knowledge about GQDs related to what properties make them interesting as nanosensors and further highlight the recent advances in their synthesis methods particularly from naturally available resources. Furthermore, fundamental sensing mechanisms will also be given to provide basic knowledge and a more comprehensive understanding to the readers about GQDs as luminescence-based biological and environmental nanosensors. The current limitations and prospects of GQDs are highlighted as the final conclusion of this review, hoping that the readers from various multidisciplinary natures to contribute their expertise and collaborate not only to improve the currently available GQD-based sensors but also to develop new sensing concepts which have never been realized.