Inventors:
Thomas Henry Vanderspurt - Glastonbury CT, US
Fabienne Wijzen - Beaufays, BE
Xia Tang - West Hartford CT, US
Miriam P. Leffler - Manchester CT, US
Rhonda R. Willigan - Manchester CT, US
Caroline A. Newman - Cromwell CT, US
Rakesh Radhakrishnan - Vernon CT, US
Fangxia Feng - Richardson TX, US
Bruce Leon Laube - South Windsor CT, US
Zissis Dardas - Worcester MA, US
Susanne M. Opalka - Glastonbury CT, US
Ying She - Worcester MA, US
Assignee:
UTC Fuel Cells, LLC - South Windsor CT
International Classification:
C01F 17/00
US Classification:
423263, 502302, 502303, 502304
Abstract:
A homogeneous ceria-based mixed-metal oxide, useful as a catalyst support, a co-catalyst and/or a getter has a relatively large surface area per weight, typically exceeding 150 m/g, a structure of nanocrystallites having diameters of less than 4 nm, and including pores larger than the nanocrystallites and having diameters in the range of 4 to about 9 nm. The ratio of pore volumes, V, to skeletal structure volumes, V, is typically less than about 2. 5, and the surface area per unit volume of the oxide material is greater than 320 m/cm, for low internal mass transfer resistance and large effective surface area for reaction activity. The mixed metal oxide is ceria-based, includes Zr and or Hf, and is made by a novel co-precipitation process. A highly dispersed catalyst metal, typically a noble metal such as Pt, may be loaded on to the mixed metal oxide support from a catalyst metal-containing solution following a selected acid surface treatment of the oxide support. Appropriate ratioing of the Ce and other metal constituents of the oxide support contribute to it retaining in a cubic phase and enhancing catalytic performance.