Author/Authors :
Madkikar, Pankaj Department of Chemistry and Catalysis Research Center - Technische Universita¨t Mu¨nchen, Germany , Wang, Xiaodong Johnson Matthey Catalysts (Germany) GmbH, Germany , Mittermeier, Thomas Department of Chemistry and Catalysis Research Center - Technische Universita¨t Mu¨nchen, Germany , Monteverde Videla, Alessandro H. A Department of Applied Science and Technology - Politecnico di Torino, Italy , Denk, Christoph Department of Chemistry and Catalysis Research Center - Technische Universita¨t Mu¨nchen, Germany , Specchia, Stefania Department of Applied Science and Technology - Politecnico di Torino, Italy , Gasteiger, Hubert A Department of Chemistry and Catalysis Research Center - Technische Universita¨t Mu¨nchen, Germany , Piana, Michele Department of Chemistry and Catalysis Research Center - Technische Universita¨t Mu¨nchen, Germany
Abstract :
We report here the synthesis of carbon-supported
ZrO2 nanoparticles from zirconium oxyphthalocyanine
(ZrOPc) and acetylacetonate [Zr(acac)4]. Using
thermogravimetric analysis (TGA) coupled with mass
spectrometry (MS), we could investigate the thermal
decomposition behavior of the chosen precursors.
According to those results, we chose the heat treatment
temperatures (THT) using partial oxidizing (PO) and
reducing (RED) atmosphere. By X-ray diffraction we
detected structure and size of the nanoparticles; the size
was further confirmed by transmission electron microscopy.
ZrO2 formation happens at lower temperature with
Zr(acac)4 than with ZrOPc, due to the lower thermal stability
and a higher oxygen amount in Zr(acac)4. Using
ZrOPc at THT >900 oC, PO conditions facilitate the crystallite
growth and formation of distinct tetragonal ZrO2,
while with Zr(acac)4 a distinct tetragonal ZrO2 phase is
observed already at THT >750 oC in both RED and PO
conditions. Tuning of ZrO2 nanocrystallite size from
5 to 9 nm by varying the precursor loading is also
demonstrated. The chemical state of zirconium was
analyzed by X-ray photoelectron spectroscopy, which
confirms ZrO2 formation from different synthesis routes.
Keywords :
Carbon-supported zirconia nanoparticles , Thermogravimetric analysis , X-ray diffraction , Transmission electron microscopy , X-ray photoelectron spectroscopy
