SURFACE STRUCTURE, REDOX PROPERTIES AND REACTIVITY OF NANO-OXIDES
WG2 members: Zbigniew Sojka, Andrzej Kotarba, Witold Piskorz, Filip Zasada, Joanna Gryboś, Paulina Indyka
homepage: www.chemia.uj.edu.pl/wydzial/zaklady/ZCHN
The research activity of the group is focused on preparation, characterization and reactivity studies of redox nano-oxides of controlled morphology and stoichiometry in the context of their catalytic applications. Experimental techniques include TEM/STEM/EDX/EELS, SEM, XRD, CW/FT-EPR, UV-vis, IR, Raman, XRF, TPD, TPR/TPO, TPSR, in situ Kelvin Probe and electric conductivity measurements To interpret experiments and the structure-reactivity relationships, cluster and periodic DFT molecular modeling is extensively used.
The oxide systems under investigation encompass nano-structured spinels (Co3O4, Mn3O4, Fe3O4,), their alkali metal derivates (KxFeO2, KxMnO2) and AO2 oxides (ZrO2, TiO2). Sensible replacement of redox cations by non-redox dopants or introduction of alien redox centers along with defect structure engineering, allow for generation of tunable model systems with the tailored redox couples of regulated strength. Their catalytic reactivity is examined for reactions with small molecules such as CO, O2, N2O,CH4 or oxidation of soot particles.
![Wulff shape predicted by DFT modeling, experimental TEM morphology viewed along the [110] zone axis, and STEM (111) surface and its simulation for cobalt spinel nano-crystal.](http://www.cost-redox.nano.cnr.it/wp-content/uploads/2013/04/zojka.png)
Wulff shape predicted by DFT modeling, experimental TEM morphology viewed along the [110] zone axis, and STEM (111) surface and its simulation for cobalt spinel nano-crystal.
