Carboxylic multi-walled carbon nanotubes are extensively used in the field of material science for enhancing the mechanical, thermal, and electrical properties of composites. They are incorporated into polymers to create lightweight yet strong materials, ideal for aerospace and automotive industries. In electronics, these nanotubes serve as conductive additives in batteries and supercapacitors, improving energy storage and efficiency. They are also utilized in environmental applications, such as water filtration systems, where their high surface area and functional groups enable effective adsorption of pollutants and heavy metals. In biomedical research, carboxylic multi-walled carbon nanotubes are explored for drug delivery systems due to their ability to functionalize with therapeutic agents and target specific cells. Additionally, they play a role in sensor technology, enhancing sensitivity and selectivity in detecting various chemical and biological substances.