Nanoscale Grain Boundary-Weakened Ce–O Covalency and Surface Confinement Intrinsically Boosting Ceria Surface Oxygen Reactivity

Promoting the reactivity of surface lattice oxygen atoms of oxide nanomaterials is critical for enhancing their catalytic performances in oxidation, hydrogenation, and electrocatalytic reactions; however, the fundamental electronic mechanisms governing this surface reactivity have long remained insufficiently understood. Here, we reveal the electronic mechanism of how the nanoscale grain boundary (GB) boosts the intrinsic surface reactivity of CeO2 nanomaterials, in which GBs are introduced by pyrolyzing the precursors of cerium carbonate and formate. The results of X-ray absorption near-edge structures (XANES) at the O K- and Ce L3-edges reveal that GBs can reduce the degree of covalency of Ce–O bonds, while…

• NN
  National Natural Science Foundation of China

  Award: 21801012, 22241502, 22035004, 22250710677