Ann: Dotz Nano Board Changes, page-3

Quick Google definition on the difference ...

Graphene quantum dots, also recognized as GQDs are disk of graphene in the size range of 2- 20 nm. They are fluorescent due to quantum confinement, surface defects and zigzag edges. GQDs are composed mainly of Sp2 hybridized carbon and they are crystalline. On the hand, Carbon dots (C-dots) are spherical carbon particles with a size less than 10 nm. They are composed mainly of Sp3 hybridized carbon, usually amorphous and they can show in XRD the (100) plane of the basal planar of graphite. Luminescence in C-Dots is due to surface defects, which explains why they quench in some medium. Also for my knowledge the difference is not much clear, if you want more information. Moreover, a lot of researcher confuse GQDs with C-Dots and other consider GQDs as a type of C-Dots. Therefore, you can consider them family of quantum dots made of carbon. Their quantum confinement is still not understood well and is not completely the same as for semiconductor quantum dots such as: CdS or CdSe. Because GQDs can have different size and same bandgap energy (i.e 3.4 eV), however, pristine graphene is 0 eV or close from 0 eV, that's why they are named as quantum dots when compared to graphene.