Application of modified cerium dioxide for photocatalytic air pollution purification

Cerium dioxide (CeO₂) is a significant rare earth oxide with the merits of rich oxygen defects, specific 4f¹5d¹ orbitals, and superior oxygen storage-release capacity in Ce⁴⁺/Ce³⁺ reversibility pairs, and has been widely investigated as an active photocatalytic material for air pollution remediation. To enhance the photocatalytic efficiency of CeO₂, recent developments of numerous modification strategies have been employed to broaden the light absorption range and reduce the recombination rate of electron–hole pairs. This review summarizes the fabrication of modified CeO₂ catalysts, including metal or nonmetal doping, heterostructure construction and oxygen vacancy manufacturing, to provide insight into how those advanced techniques improve the photocatalytic activity. Moreover, this work provides a detailed discussion on the usage of modified CeO₂ in the fields of air pollution control, including nitrogen oxides removal, volatile organic compounds elimination and the purification of carbon dioxide. Finally, the potential future development and further research on the modification of CeO₂ has been identified.