Scalable Approach for Fabricating Thermally Stable, Low-Temperature Catalysts

Abstract

Researchers at the University of Central Florida have developed a low-cost, scalable approach for using any reducible metal oxide or mixed metal oxide materials to fabricate thermally stable, low-temperature catalysts. The UCF invention offers a solution for automakers tasked with meeting increasingly stringent emissions standards. For example, future catalytic systems will need to remove more than 90 percent of the pollutants from gas and diesel engine exhaust such as hydrocarbons, carbon monoxide or nitrogen oxides. Also, catalytic systems will need to operate at relatively low temperatures (at or below 150 degrees Celsius) and must be durable enough to survive the harsh conditions of automotive exhaust.

Technical Details

The invention comprises methods for producing metal or metal oxide catalysts for a variety of applications. One method provides highly stable reducible metal oxide support structures for precious metal anchoring. The other method generates engineered surface defects on reducible metal oxides that can result in highly active and stable single site, nanocluster or nanoparticle catalysts.

In one example application, scientists use the invention’s unique multi-step incipient wetness impregnation (IWI) process to fabricate reducible metal oxide support structures. For instance, IWI of CeO₂ on Al₂O₃ followed by high-temperature calcination (heating at approximately 800 degrees Celsius in an oxygen-rich environment), may produce a surface layer of CeAlO₃ with excellent thermal stability. Next, the scientists use a gas-phase reducing agent to generate multiple defect sites on the surface of the reducible metal oxide support structures. The surface defects are stable at room temperature even under atmospheric conditions and may serve as thermally stable anchor sites for loaded metals or metal oxides. Precious metals or base metals/metal oxides anchored to the engineered surface defects exhibit high catalytic activity and provide high catalytic performance.

Examples of metals or metal oxides that are usable as catalysts include precious metals (such as platinum, palladium, rhodium, iridium or gold) as well as transition metals or relative metal oxides, including copper, nickel, iron or cobalt. Reducible metal oxides may include single metal oxides such as ceria, iron oxide, manganese oxide, or copper oxide, or mixed metal oxides like ceria zirconia, copper-cerium oxide or iron-cobalt oxide.

Partnering Opportunity

The research team is looking for partners to develop the technology further for commercialization.

Stage of Development

Prototype available.

Benefit

Market Application