Cerium oxide and its nanocomposites: Structure, synthesis, and wastewater treatment applications

Pollutants are posing a severe threat to the environment. These toxic pollutants are quite carcinogenic and neurogenic. Therefore, methodologies are continuously improving for the effective removal of contaminants from wastewater using various metal-oxide-based nanocomposites. In this regard, different metal oxides, such as ZnO, TiO 2 , and CeO 2 based-nanocomposites have been developed and utilized for the cost-effective degradation of various organic pollutants from water. This review focused on the degradation of organic pollutants by heterogeneous doped cerium oxide-based nanocomposites. Pristine cerium oxide was doped with other nanocomposites to lower its bandgap, resulting in the enhancement of photocatalytic activity. This review focused on the mechanism of pristine ceria and doped ceria for the degradation of various pollutants. Various methodologies used to synthesize CeO 2 -based nanocomposites for the effective degradation of contaminants are emphasized and discussed in this article. This review focused on the recent development of cerium-oxide-based nanocomposites for the effective degradation/removal of various pollutants from water. This manuscript also visualizes the challenges from the future regarding the photocatalytic performance of different CeO 2 doped nanocomposites.