Degradation Behaviorof CeO₂‑BasedNanoparticles as Oxygen Carriers for the Chemical Looping Process

In this study, we investigated the degradation behavior of CeO₂-based nanoparticles as oxygen carriers for the chemical looping process. In the investigation of the dependency of the reaction gases on the degradation in terms of changes in the CeO₂ crystallite, H₂O and H₂ caused the most significant increase in the crystallite size (sintering) compared with other gases. It was found that Pt decoration, a well-known method for the enhancement of performance as an oxygen carrier, was effective in suppressing the sintering in various reaction gases. On the other hand, mixing with ZrO₂ nanoparticles that are not reactive as oxygen carriers also improves the durability of CeO₂. The sintering-prevention effect of mixing ZrO₂ nanoparticles as nano-obstacles also contributes to exploiting the intrinsic catalytic activity of CeO₂ nanoparticles. Mixing with other nanomaterials would be a universal strategy for improving the durability and activity of thermodynamically unstable nanocatalysts.