Oxygen vacancy distributions and electron localization in a CeO₂(100) nanocube

Abstract

Oxygen vacancy distributions in a 5 nm CeO2 nanocube were determined using the Reverse Monte Carlo method. The oxygen vacancies tend to be located on the surface of the CeO2 nanocube, with far fewer in subsurface and internal regions.

Coupling Metal and Support Redox Terms in Single-Atom Catalysts

“…These effects were used to rationalize the global minimum structure for defective (100), reported as a surface vacancy with two surface polarons located at the nearest neighbor (NN) positions to the vacancy. 56,57 By considering all symmetry-inequivalent distributions of two surface polarons on defective, unreconstructed CeO 2 (100) in our p(3 × 3) supercell, we obtain vacancy formation energies of 1.40−2.30 eV, in line with previously reported results. 20,50,56,58 The significant influence of the computational setup on the ordering of individual states should be noted 56,59 and is further discussed in Note S1.…”

“…The stabilities of the defective surfaces, and thus vacancy formation energies, are determined by several geometric properties, which can be summarized as follows: (i) the ability of the lattice to adjust for the more spacious, reduced Ce 3+ centers, (ii) the accommodation of oxygen distortions toward the newly formed empty site, and lastly, (iii) the repulsion between the Ce 3+ centers. These effects were used to rationalize the global minimum structure for defective (100), reported as a surface vacancy with two surface polarons located at the nearest neighbor (NN) positions to the vacancy. , …”

Insights into CO Oxidation in Cu/CeO2 Catalysts: O2 Activation at the Dual‐Interfacial Sites

“…The U value of 5.0 eV was employed to correctly describe the 4 f electrons of Ce ions, following our previous study. [14,29] The climbing image nudged elastic band (CI- NEB) algorithm was preformed to search the transition states for CO oxidation. [30] Vibrational frequency analysis was used to further confirm the identified transition state.…”

Effects of Subsurface Oxide on Cu1/CeO2 Single-Atom Catalysts for CO Oxidation: A Theoretical Investigation

“…7−9 Theoretically, the (111), (110), and (100) planes of CeO 2 are the three most thermodynamically stable lowindex crystal faces. 10 Therefore, the CeO 2 terminal faces with various surface energies [i.e., (100) > (110) > ( 111)] has been one of the most attractive topics in the study of surface effects. In addition, the relationships between catalytic reactivities and exposed faces of M/CeO 2 catalysts (such as Au, Pt, Pd, etc.…”

“…In heterogeneous catalysis, the interaction between supported metals and metal-oxide surfaces is a key to understand catalytic performances. , Among the various metal-oxide support materials, CeO 2 is one of the most widely used supports due to the abundant oxygen vacancies and can stably anchor nano clusters and single atoms. − Experimentally, synthesized CeO 2 nanoparticles usually have three morphologies, nano-octahedron with (111)/(110) terminated surfaces, nano-rod exposed (110)/(100) surfaces, and nano-cube with (100) terminated surfaces. − Theoretically, the (111), (110), and (100) planes of CeO 2 are the three most thermodynamically stable low-index crystal faces . Therefore, the CeO 2 terminal faces with various surface energies [i.e., (100) > (110) > (111)] has been one of the most attractive topics in the study of surface effects.…”