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

Cerium oxide (CeO 2 ), 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 Ce 3+ concentration in CeO 2 restricts the activities of haloperoxidase mimicry, which hinders its application. Here, CeO 2 was loaded onto carbon nanotubes (CNTs), where dopamine hydrochloride (DA) was polymerized as the "linker" and CNTs the "skeleton." Two types of samples, termed CeO 2 -CNT (CeO 2 49@PDA/CNT and CeO 2 77@PDA/CNT), were prepared and CeO 2 was found to be uniformly distributed on CNTs, and their Ce 3+ and oxygen (O) vacancy concentrations analyzed. CeO 2 77@PDA/CNT, with the higher Ce 3+ 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 CeO 2 with CNTs as the skeleton.