Jinrui Zhang, Xiaozhi Liu, Yue Pan, Yue Pan, Peng Li, Yuanhui Shen, Yuhan Wang, Tianlong Yang, Dong Su, Ying Pan, Ying Pan, Hongguang Jin
Chemical looping dry reforming of methane holds great promise for both CO 2 utilization and syngas production with high efficiency. The structure and composition of oxygen carriers are critical factors influencing CL-DRM performance. Incorporating CeO 2 is known to enhance the reactivity and stability of Fe 2 O 3 in chemical looping reforming. However, the underlying mechanism of how CeO 2 synergistically interact with Fe 2 O 3 to enhance performances remains unclear. In this work, we comparatively investigated CeO 2 -supported Fe 2 O 3 OCs in interfacial and physical Fe–Ce contact modes. We found the sol–gel-synthesized Fe 2 O 3 /CeO 2 OC is in-situ activated within the first cycle and transforms to pure CeFeO 3 through a strong Fe 2 O 3 –CeO 2 interaction. The activated CeFeO 3 achieves over 80% CH 4 conversion, 96% CO selectivity, and excellent stability due to the sufficient Fe–Ce interaction, proper valence state, and low-energy barrier for oxygen diffusion. Additionally, in-situ environmental transmission electron microscopy study shows that the Fe 2 O 3 –CeO 2 interaction promotes the oxygen release of both oxides during reduction. Under the oxidative conditions, iron exhibits significant activity to dissolve into the CeO 2 lattice and form CeFeO 3 . The investigation into the activation mechanism of the Fe 2 O 3 /CeO 2 material provides valuable insights for designing straightforward and cost-effective OCs.