Carbon dots derived from natural sources and their biological and environmental impacts

Abstract

Carbon dots (CDs) have successfully stood out among numerous materials, attributed to their superior characteristics, including ultra-small size, good photostability, excellent biocompatibility, and tunable fluorescence property. Accompanied by their remarkable performance, emerging concerns regarding the increasing possibility of CDs entering the ecology grow. It has become a relevant task to conquer the bottleneck of CD preparation and face the challenges including environmental deterioration and non-renewable resource consumption. CDs derived from natural sources have recently attracted significant attention and demonstrated great potential as promising substitutes for various applications. This review focuses on the CDs derived from natural sources and their biological and environmental impacts. We first provide an overview of various raw materials, including biomass and biomass waste, that can be employed for the preparation of CDs, together with their feature synthesis procedures. Then, we systematically introduce the impacts of CDs on humans and the environment from both positive and concerning aspects, such as the promising applications in biomedicine and the potential risk to the function of biomolecules. Finally, we discuss the ongoing challenges and give a future perspective for thoroughly evaluating the influence of CDs derived from natural sources on our daily life.