Design strategies for ceria nanomaterials: untangling key mechanistic concepts

Abstract

The present work provides a comprehensive array of design parameters for the fabrication of the principal morphologies of nanoceria.

Decoupling the Impacts of Engineering Defects and Band Gap Alignment Mechanism on the Catalytic Performance of Holey 2D CeO2−x‐Based Heterojunctions

“…Further, it is likely that this process is assisted by the ready transformations between the Magnéli‐like Mo–O shear structures (Figure S3, Supporting Information), [ 43 ] which also are known in the systems Ti–O, [ 44 ] Ce–O, [ 22 ] W–O, [ 45 ] and Sn–O. [ 46 ] It is considered likely that the final Mo valence is 4+ owing to its much greater stability, as suggested by its melting point of 2300 °C, than those of Mo 5+ and Mo 6+ , which exhibit peritectic decomposition in the temperature range 800–818 °C.…”

“…[68] The experimental E g of 2.73 eV is considerably less than the typical literature value of 3.00 eV [69] and less than the value of 3.2 eV calculated by DFT (Figure S10, Supporting Information). According to Xu et al, [22] the E g can be calculated on the basis of the [VO…”

“…[20] In acidic media, the potential is in the range of 1.3-1.8 V. [21] The capacity for interstitial solid solubility doping of CeO 2−x with cations is high owing to the large central interstice (ionic radius 0.110 nm) and the large interstice (0.160 nm) in the repulsive Ce sublattice. [22,23] However, doping also can result in the formation of secondary phases. For Mo doping, the MoO 3 -CeO 2 phase diagram shows that both Ce 2 (MoO 4 ) 3 and Ce 2 (MoO 3 )(MoO 4 ) 3 can form.…”

Solvothermal Synthesis Routes to Substituted Cerium Dioxide Materials

“…Finally, scale-up of synthesis requires further consideration, bearing in mind the complex mixtures of reagents being used to tailor the crystal form. [194]; purple = from the literature; [Ce]: low < 0.50 M ≤ high; [NaOH]: low < 5.00 M ≤ high; T: low < 150 • C ≤ high; t: short ≤ 2 h < long) [194]. Reproduced from Xu, Y.; Mofarah, S.S.; Mehmood, R.; Cazorla, C.; Koshy, P.; Sorrell, C.C.…”

“…This has recently been examined for CeO2 itself [193], but there is much further work to be conducted in this respect. Finally, we note that in the case of CeO2 itself, a recent article by Xu et al extensively reviewed the various solution methods for synthesis, including solvothermal methods, and attempted to classify the various influences on crystal growth with the aim of having some predictability in the control of the crystal form, Figure 21 [194]. While the addition of a substituting cation, and indeed habit-modifying additives, introduces further complexity, it is highly likely that the same principles put forward will apply to the wider family of cerium oxide materials.…”