New trends in nonconventional carbon dot synthesis

Carbon dots (CDs) are currently one of the hot topics in the nanomaterial world. Until recently, their preparation has been mostly based on solvothermal or hydrothermal syntheses requiring high temperatures, long reaction times, or toxic solvents. Moreover, the resulting materials are often affected by low reproducibility and difficult purification. A potential solution to these problems could be represented by innovative fields of chemistry, such as mechanochemistry, flow chemistry, and laser synthesis in the liquid phase. Machine learning could also be applied to go beyond the trial-and-error approach commonly used to explore the CD chemical space. In this review, we explore these recent approaches and their future potential to address some of the CD limitations, widening the range of properties and applications of these highly promising nanomaterials.