Eco‐Friendly Walnut Shell Agro‐Waste‐Derived CQDs for Insecticide Sensing, Anti‐Inflammatory, and Cytotoxic Studies

In the current situation, turning agro-waste into valuable products is essential and requires confidence to work with. To illustrate this notion, we transformed one of the biomass agro-wastes, Walnut Shell (WS), into Carbon Quantum Dots (CQDs) material with unique properties, for utilizing insecticide detection, and anti-inflammatory and cytotoxicity studies. WS is a non-toxic waste material with high carbon content that has been employed in the hydrothermal preparation of CQDs. CQDs are zero-dimensional (0D) fluorescent carbon-based nanomaterials and have gained global attention due to their great optical qualities, water solubility, compatibility with living organisms, low toxicity, eco-friendliness, and easy synthesis methods. The as-prepared WS-CQDs were characterized by standard physicochemical methods for understanding their crystalline nature, morphology, size, electronic state, functional groups, element composition, and optical properties. Based on the aforementioned information, this chapter addresses the agriculture and biological applications and optoelectronic properties of WS-CQDs.