<p>This research investigates the synthesis and catalytic performance of Nd-doped Co₃O₄ nanoparticles for the selective oxidation of styrene to benzaldehyde. The incorporation of Nd³⁺ ions into the Co₃O₄ lattice led to structural modifications. XRD analysis confirmed the formation of a spinel structure with the successful incorporation of Nd³⁺ ions into the Co₃O₄ lattice. SEM and TEM images revealed morphology of compound. UV-DRS analysis showed a blue shift in the band gap with increasing Nd doping. Photoluminescence studies indicated the presence of oxygen vacancies and their reduction with increasing Nd concentration. The catalytic activity of the Nd-doped Co₃O₄ catalysts was evaluated under various reaction conditions. The enhanced catalytic performance was attributed to the synergistic effect of Nd³⁺ doping, which increased the number of active sites and improved the redox properties of the catalyst. This work provides valuable insights into the design and development of efficient catalysts for selective oxidation reactions.</p>