Engineering cerium oxide nanoparticles for tunable wettability properties

The synthesis and design of nanomaterials with distinctive physical and chemical properties provides novel opportunities to utilize them in various applications. Nanomaterials’ structures and surface characteristics significantly influence their physicochemical properties. These properties can be modified by tuning their synthesis reaction parameters. Here, we provide a simple and effective wet chemical method for the controlled synthesis of cerium oxide nanoparticles (CeO2 NPs) functionalized with citric acid or Cetrimonium bromide (CTAB) as the capping agents. The synthesized CeO2 NPs were characterized using XRD, Raman spectroscopy, FESEM, TEM, and FTIR to study the crystal structure, morphology, and functional groups. The CeO2-capping agent molecules were found to be arranged in a crystalline cubic lattice in the nanoparticles. We investigated the surface wettability for various functionalized CeO2 NPs by contact angle measurements. We found that the morphology and hydrophobicity of the NPs could be changed by changing the capping agent. The functionalization of CeO2 with CTAB resulted in maximum enhancement in the hydrophobicity with a contact angle of 92.2 ± 3.3°. This work provides valuable insights into surface functionalization of CeO2 NPs as a method to modulate their morphology and wetting characteristics.