Peroxidase-like Catalytic Mechanism of CeO2-based Nanozymes and Their Colorimetric Sensing Applications

Over the past few decades, a multitude of artificial enzymes have been investigated. With the development of nanoscience, nanozymes have attracted widespread attention of researchers because they can solve the issues of insufficient activity of traditional artificial enzymes. As one of the most interesting and important rare earth oxides in catalysis, CeO2 exhibits excellent peroxidase-like activity due to its fast Ce4+ & LRARR; Ce3+ redox switch and the existence of related oxygen vacancies. However, the combination of CeO2 with other materials to form CeO2-based nanozymes is beneficial to improve the catalytic performance. This review introduced a variety of CeO2-based nanozymes, discussed their peroxidase-like catalytic mechanisms, kinetics, and colorimetric sensing applications. Finally, the current challenges and potential future directions of CeO2-based nanozymes were summarized.