The Role of Carbon Quantum Dots in Environmental Protection

Abstract Now more than ever, research into environmental management has gained relevance. Carbon quantum dots (CQDs) have recently been considered a valuable asset to this field, as their tunable fluorescence, adaptable surface chemistry and behavior as both electron acceptors or donors are chemical properties of paramount importance. This newfound interest emerged in the scientific community, and propelled CQDs to be utilized in diverse strategies for environmental remediation and pollution containment. Thus, this review will thoroughly examine how the several stages of CQDs life cycle can be exploited in the protection of the environment and hence, have a role in the Sustainable Development Goals of the United Nations. Starting with their production, several techniques for green synthesis of CQDs resorting to biomass and waste products will be discussed. Then, the applications of CQDs in pollution sensing, degrading, and adsorbing will be the focus. The role of CQDs in clean energy generation will also be described, namely their inclusion in solar cells, solar‐thermal convertors, and hydrogen evolution processes. Lastly, current challenges and limitations to the widespread use of CQDs will be addressed, followed by considerations on the contribution that CQDs may provide upon their pervasive implementation.