Light on multicolor fluorescent carbon dots from a single biomass precursor through simply tuning the solvothermal temperature and time strategy

The conversion of biomass to carbon-based nanomaterials has recently received increasing attention, thanks to in line with the ideas of environmental protection and sustainable chemistry. Up to now, facial and fast synthesis of a single biomass precursor-derived carbon dots (CDs) with tunable multicolor fluorescence remains a challenge. Herein, we select mosses as cheap, abundant, and renewable biomass to prepare CDs with multicolor fluorescence by simply tuning solvothermal temperature and time. Through the characterization and comparison of a series of moss-derived CDs, it is revealed that the reaction temperature and time can effectively control the ratio of chlorophyll as the red luminescence center and carbon-core states as the blue luminescence center. Moreover, strong emission in the deep red light region, low toxicity, and outstanding biocompatibility made m-CD180 suitable for cellular imaging. This study provides a simple method for the green utilization of mosses and also provides a new idea for the fluorescence regulation and application of biomass-derived CDs.