Carbon dots as sustainable nanomaterials: Fabrication strategies, properties, characterisation, and applications: A systematic review

This review discusses different types of carbon dots and synthesis methods, including hydrothermal, microwave, pyrolysis, electrochemical, and ultrasonic techniques. It highlights green synthesis using plant and biomass materials as eco-friendly approaches. CDs are characterized using techniques like UV-Vis, FTIR, XRD, TEM, SEM, XPS, photoluminescence and zeta potential. Recent applications in drug delivery, bioimaging, biosensing, heavy metal detection, environmental remediation, agriculture, food safety, photocatalysis and energy-related fields are comprehensively reviewed. However, challenges such as limited understanding of fluorescence, large-scale production, and clinical use. Future research should focus on controlled synthesis, red/NIR CDs, and sustainable production. Overall, CDs have strong potential for future applications.