Novel Reducibility‐tunable Carbon Dots for Efficient Radicals Scavenging and Material‐controlled Synthesis

The development of efficient, nontoxic and low‐cost nano‐antioxidants has attracted extensive attentions in food preservation, but still remains greet challenges in materials design and mechanism exploration. Herein, a novel reductive carbon dots (r‐CDs) was successfully synthesized via a simple pyrolysis technique using sucrose as the precursor. The experimental results show that r‐CDs possess excellent reducibility, and can effectively scavenge a variety of reactive oxygen and nitrogen species (RONS). So, the r‐CDs exhibits remarkable preservation effect on apple and strawberry, and significantly extends their shelf‐life. Mechanistic studies reveal that their outstanding reducibility/antioxidant property is attributed to the formed carbon‐core and numerous hydroxyl groups in the pyrolysis process. More interestingly, the reducibility of r‐CDs can be gradually regulated by nitrogen doping, the obtained N‐doped CDs (N‐CDs) can be used to synthesize gold nanomaterial with different morphology and size, proving its potential applications in material‐controlled synthesis. This study provides a new idea for the development of non‐toxic, efficient carbon nano‐antioxidants with tunable reducibility for food preservation and material‐controlled synthesis.