Bioresource-Derived Graphene Quantum Dots: A Tale of Sustainable Materials and Their Applications

Carbon is an elite element when coming to the material research field [1]. Carbon has delivered numerous useful nanostructures including carbon nanotube [2], graphene, etc. [3]. The history of carbon nanomaterials began with the synthesis of graphene oxide from graphite, and it was named as ‘graphon’ in the older time [4]. Then a large number modified synthetic procedures were developed for the production of graphene oxide in bulk quantity [5]. Along with these developments, the invention of fullerene, an important allotrope of carbon, occurred [6], and it was followed by the discovery of one-dimensional carbon nanotubes [7]. At the same time, the existence of single sheet of graphite was a hot topic of debate, and its existence was only theoretical until in 2011 the monolayer graphene through scotch-tape technique was synthesized [8]. The other important carbon nanomaterials invented include nano-horns [9], nano-onions [10], etc. Thus, the carbon nanomaterial family included members in various dimensions ranging from zero to three.