Exploring Ce3+/Ce4+ cation ordering in reduced ceria nanoparticles using interionic-potential and density-functional...

Area of Science:

• Materials Science
• Computational Chemistry
• Nanotechnology

Background:

• Atomistic simulations are crucial for understanding nanoparticle properties.
• Ceria (CeO2) nanoparticles are vital in catalysis and as solid oxide fuel cell electrolytes.
• Accurate modeling of cerium's mixed valence states (Ce3+/Ce4+) is computationally challenging.

Purpose of the Study:

• To evaluate the performance of interionic potentials against density-functional theory (DFT) for ceria nanoparticle isomer modeling.
• To compare the structural and energetic predictions of classical potentials with LDA+U and GGA+U DFT methods.
• To determine the feasibility of using interionic potentials for efficient ceria nanoparticle configuration screening.

Main Methods:

• Atomistic calculations using interionic potentials.
• Density-functional theory (DFT) calculations with LDA+U and GGA+U functionals.
• Analysis of structural parameters and relative energies for ten Ce19O32 configurational isomers.

Main Results:

• Interionic potential calculations closely reproduced the relative energy ordering and structural trends of DFT methods.
• Good agreement was observed in cation-cation distances and isomer stability.
• The accuracy stems from a balance between electrostatic and bonding interactions, not a single dominant force.

Conclusions:

• Interionic potentials provide a reliable and computationally efficient method for predicting stable Ce3+/Ce4+ cationic orderings in ceria nanoparticles.
• This approach can significantly accelerate materials discovery by preselecting promising configurations.
• Classical potentials offer a valuable alternative to high-cost DFT for initial screening of ceria nanoparticle structures.