Method for preparation of nanometer cerium-based oxide particles
US7025943B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 2002 |
| Grant date | Apr 11, 2006 |
| Priority date | — |
| Expiry date | May 27, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2982
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention comprises novel undoped and doped nanometer-scale CeO2 particles as well as a novel semi-batch reactor method for directly synthesizing the novel particles at room temperature. The powders exhibited a surface area of approximately 170 m2/g with a particle size of about 3–5 nm, and are formed of single crystal particles that are of uniform size and shape. The particles' surface area could be decreased down to 5 m2/g, which corresponds to a particle size of 100 nm, by thermal annealing at temperatures up to 1000° C. Control over the particle size, size distribution and state of agglomeration could be achieved through variation of the mixing conditions such as the feeding method, stirrer rate, amount of O2 gas that is bubbled through the reactor, the temperature the reaction is carried out at, as well as heating the final product at temperatures ranging from 150° to 1000° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.