Metallosurfactant Ionogels in Imidazolium and Protic Ionic Liquids as Precursors To Synthesize Nanoceria as Catalase Mimetics for the Catalytic Decomposition of H2O2

Graphical From gels to catalysts : Ionogels formed by metallosurfactants with different counterions in imidazolium ionic liquids and protic ethylammonium nitrate are discussed. The microstructures of the ionogels are lamellar phases and characterization results indicate that the characteristics of imidazolium ionic liquids have great effects on the ionogel properties. The ionogels were employed as precursors to prepare CeO 2 nanoparticles, which exhibited good catalase mimetic activity (see figure). The gelation behavior of cationic surfactants with different counterions, Br − , [FeCl 3 Br] − , and [CeCl 3 Br] − , in imidazolium ionic liquids (ILs) and protic ethylammonium nitrate was investigated. Small-angle X-ray scattering measurements and freeze-fracture transmission electron microscopy observations revealed the lamellar phases of metallosurfactant ionogels. The characteristics of imidazolium ILs, including the size and type, have effects on metallosurfactant ionogel properties, such as transformation temperatures, interlayer spacing, and mechanical strength. Cubic fluorite structured cerium oxide nanoparticles (CeO 2 NPs) were produced by using metallosurfactant ionogels as precursors. Cubic fluorite CeO 2 exhibited good catalase mimetic activity toward H 2 O 2 to generate O 2 , providing more multiple mimetic enzyme activities of CeO 2 NPs for H 2 O 2 .