Researchers from Rice University, together with colleagues in China, India, Japan and Texas, discovered a new one-step wet chemical process that turns carbon fiber into graphene quantum dots. The process enables making the GQDs in bulk - which are highly soluble.

The size of the QDs can be controlled via the temperature at which they're created. At 120 degrees they got a blue QD, at 100 a green one and a 80 degrees - a yellow QD.