Enhancing Ceria Nanoparticle Properties Through Neodymium Doping: A Comprehensive Study

Efficient energy storage is essential for sustainable technological development, with supercapacitors emerging as a promising solution due to their high power density and long cycle life. To enhance their electrochemical performance, the discovery and optimization of advanced electrode materials are critical. Cerium oxide (CeO₂) has recently gained attention, particularly when doped with rare-earth elements such as neodymium (Nd). This study investigates the structural, morphological, and electrochemical properties of Nd-doped CeO₂ synthesized via the glycine combustion method with Nd concentrations of 3, 6, and 9 mol%. Crystalline structure was characterized using X-ray diffraction (XRD), Rietveld refinement, and Raman spectroscopy. All samples exhibited a face-centered cubic (fcc) lattice, and Raman analysis confirmed that Nd incorporation maintained the structural integrity while inducing oxygen vacancies. Morphological analysis via field emission scanning electron microscopy (FESEM-EDS) and Brunauer–Emmett–Teller (BET) measurements revealed nanoparticles with sizes below 100 nm and uniform elemental distribution aligned with the target doping levels. Electrochemical behavior was assessed through cyclic voltammetry. The 3 mol% Nd-doped CeO₂ sample demonstrated the highest specific capacitance of 40 F g⁻¹, attributed to its optimized defect structure and enhanced surface characteristics. These findings suggest that Nd-doped CeO₂, particularly at low doping concentrations, holds significant promise as an efficient electrode material for next-generation supercapacitor applications.