Carbon Quantum Dots (CQDs), representing zero-dimensional carbon nanostructures, have garnered significant attention across a spectrum of scientific disciplines. Their prominence can be attributed to a unique set of attributes, including photoluminescent properties, low toxicity, chemical and physical stability, eco-friendly synthesis routes, multifunctionality, and extraordinary nanoscale dimensions. This study takes a comprehensive approach, seamlessly integrating experimental and theoretical methodologies to provide an in-depth exploration of CQDs.

CQDs were synthesized using plant residues as precursors, utilizing materials such as fruit peels and seeds from lemon, avocado, and watermelon, all through a sustainable hydrothermal process. This method, designed to yield CQDs, is both environmentally friendly and characterized by its simplicity and cost-effectiveness. Comprehensive characterization of these nanomaterials was conducted using a wide range of sophisticated spectroscopic techniques, including UV-Vis, FTIR, Raman, SEM, AFM, and XPS, offering profound insights into their molecular composition. Furthermore, Density Functional Theory (DFT) was employed to delve into their spectroscopic behavior.

In addition to their intriguing structural and chemical properties, Carbon Quantum Dots (CQDs) also serve as a versatile platform for biocompatible drug delivery, providing precise control and real-time monitoring capabilities. This research bridges the realms of basic, life, and environmental sciences in the context of climate change, biodiversity, and sustainability. It also aligns with the biological applications of chemistry and phytochemistry, showcasing the potential of plant-based materials in the synthesis of eco-friendly nanomaterials with promising biomedical applications.

Key words: Carbon Quantum Dots, Hydrothermal synthesis, Sustainable Synthesis, Plant Residues, Plant Residues.

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