This investigation explores the impact of synthesized cerium oxide nanoparticles (CeO NPs) on the solvatochromic behaviour and fluorescence resonance energy transfer (FRET) of the compound 5-phenyl-1-pyridine-3-yl-penta-2,4-dien-1-one in various solvents. The dipole moments of this compound have been estimated using theoretical and experimental methods. Furthermore, the analysis of CeO NPs concentration on the organic fluorophore was conducted using the Benesi-Hildebrand equation, the findings indicated a substantial transfer of energy between CeO NPs and 5PPD.