Synthesis and characterization of new CNT-loaded CeO2 nanoparticles for antibacterial applications

Cerium oxide (CeO2), with haloperoxidase mimic activity, has attracted attention because it can break through many limitations of biological enzymes as a green and efficient antibacterial agent. However, low Ce3+ concentration in CeO2 restricts the activities of haloperoxidase mimicry, which hinders its application. Here, CeO2 was loaded onto carbon nanotubes (CNTs), where dopamine hydrochloride (DA) was polymerized as the "linker" and CNTs the "skeleton." Two types of samples, termed CeO2-CNT (CeO249@PDA/CNT and CeO277@PDA/CNT), were prepared and CeO2 was found to be uniformly distributed on CNTs, and their Ce3+ and oxygen (O) vacancy concentrations analyzed. CeO277@PDA/CNT, with the higher Ce3+ and O vacancy concentration, showed excellent antibacterial performance, up to 98.03%. This study demonstrated a method for enhancing the activities of haloperoxidase mimicry and antibacterial performance of CeO2 with CNTs as the skeleton.