Sonoelectrochemistry, Sonoelectrocatalysis, and Ultrasonic Heterogeneous Catalysis in a Thin Layer
- Detailed Technology Description
- This technology is asonoelectrolytic device comprising electrodes in a thin layer of electrolyte.In a bulk fluid, sound energy is dissipated and poorly captured at theelectrode surface. Sonoelectrochemistry in a thin layer allows sound energy captureat electrodes as sound reflects at the air interface back into the fluid andelectrodes. Parasitic energy cost of ultrasound is very low because voltage,not current, drives ultrasonic transducers. Lower energy costs for thetransducers may enable less noble metals to be used as electrocatalysts. Polymertransducers can also pump reactants in and products in the cell. This technology is based on theenergetics of cavitation, where formation and collapse of small bubbles inducedby ultrasound generates local extremes of temperatures and pressure. Ultrasoundin a thin layer drives large increases in electrode reaction rates withoutobserved cavitation; this requires little input energy and yields readilyinterpreted electrochemical signals consistent with greater efficiency. Thinlayer sonoelectrochemistry enhances oxygen reduction reaction ORR kinetics andthereby reduces the energetic tax of otherwise observed kinetic limitations. Preciousmetal catalysts and electrodes may be eliminated. This increase in electrode reactionrates has broad applications in electrosynthesis and energy technologies, suchas batteries and fuel cells. This technology will help broadly decrease costsfor electrosynthesis, which will impact critical technologies and materialssuch as chloroalkali production and aluminum refining.
- *Abstract
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Patent information: Pending
Background Information
Proton exchange membrane fuel cells convert chemical energy of fuel into electrical energy by reactions of fuel at anodes and oxidizer at cathodes. Thermodynamically, fuel cells provide excellent portable power because highly energetic, low molecular weight, renewable species serve as fuel and oxidant. But, fuel cells operate far below theory as electrode reaction rates are slow, even with precious metal catalysis. Here, electrode rates are increased with ultrasound. Ultrasonic irradiation in a thin fluid layer captures energy at electrodes to increase rates and, thereby power, energy, and efficiency. Effective ultrasonic, thin layer electrocatalysis is demonstrated for reactions important in electrochemical power and energy systems (fuel cells and batteries) and electrosynthesis. This includes markedly enhanced kinetics for the oxygen reduction reaction ORR and methanol electrolysis. These results anticipated better enabled energy technologies (e.g., metal air batteries and direct reformation fuel cells) and critical industrial technologies (e.g., chloralkali synthesis and aluminum refining).
Technology Summary
This technology is a sonoelectrolytic device comprising electrodes in a thin layer of electrolyte. In a bulk fluid, sound energy is dissipated and poorly captured at the electrode surface. Sonoelectrochemistry in a thin layer allows sound energy capture at electrodes as sound reflects at the air interface back into the fluid and electrodes. Parasitic energy cost of ultrasound is very low because voltage, not current, drives ultrasonic transducers. Lower energy costs for the transducers may enable less noble metals to be used as electrocatalysts. Polymer transducers can also pump reactants in and products in the cell.
This technology is based on the energetics of cavitation, where formation and collapse of small bubbles induced by ultrasound generates local extremes of temperatures and pressure. Ultrasound in a thin layer drives large increases in electrode reaction rates without observed cavitation; this requires little input energy and yields readily interpreted electrochemical signals consistent with greater efficiency. Thin layer sonoelectrochemistry enhances oxygen reduction reaction ORR kinetics and thereby reduces the energetic tax of otherwise observed kinetic limitations. Precious metal catalysts and electrodes may be eliminated. This increase in electrode reaction rates has broad applications in electrosynthesis and energy technologies, such as batteries and fuel cells. This technology will help broadly decrease costs for electrosynthesis, which will impact critical technologies and materials such as chloroalkali production and aluminum refining.
Advantages
- High efficiency, low cost
- Low parasitic energy cost for transducers
- Enables energy storage and generation technologies such as low temperature direct reformation fuel cells (e.g. DMFCs) and metal air batteries
- Broadlydecreases costs for electrosynthesis
- *Licensing
- Sean KimSenior Licensing AssociateUniversity of Iowa Research FoundationPh: 319-335-4607hyeon-kim@uiowa.edu
- Country/Region
- USA
