Equilibrium oxygen storage capacity of ultrathin CeO_2-δ depends non-monotonically on large biaxial strain.

ABSTRACT: Elastic strain is being increasingly employed to enhance the catalytic properties of mixed ion-electron conducting oxides. However, its effect on oxygen storage capacity is not well established. Here, we fabricate ultrathin, coherently strained films of CeO_2-δ between 5.6% biaxial compression and 2.1% tension. In situ ambient pressure X-ray photoelectron spectroscopy reveals up to a fourfold enhancement in equilibrium oxygen storage capacity under both compression and tension. This non-monotonic variation with strain departs from the conventional wisdom based on a chemical expansion dominated behaviour. Through depth profiling, film thickness variations and a coupled photoemission-thermodynamic analysis of space-charge effects, we show that the enhanced reducibility is not domin

SUBMITTER: Balaji Gopal C 

PROVIDER: S-EPMC5454370 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature