Renewable synthetic fuels by electro- or thermo-catalysis?
Event details
| Date | 01.03.2018 |
| Hour | 10:30 › 11:30 |
| Speaker |
Dr. Andreas Borgschulte Laboratory 502 Advanced Analytical Technologies Empa - Swiss Federal Laboratories for Materials Science & Technology Dübendorf, Switzerland |
| Location | |
| Category | Conferences - Seminars |
ChE-605 - Highlights in Energy Research seminar series
State-of-the-art production of renewable hydrocarbons may be divided into three steps: light harvesting and conversion to electricity (photovoltaics), water electrolysis, and conversion of the hydrogen to hydrocarbons by catalytic reaction with CO2. Electrolysis is an electro-chemical process taking place at two spatially separated electrodes. The Faraday efficiency for water electrolysis is near one; the voltage–current relation is thus sufficient to characterize the water-splitting reaction and defines the overall efficiency, which reaches more than 80% in modern electrolyzers. The efficiency of the subsequent step, the catalytic reaction of hydrogen with CO2 to produce hydrocarbons, depends on thermodynamic factors (Gibbs free energy) and kinetic constraints requiring elaborated temperature/pressure and additional separation and/or cycling procedures. The effort of the required various technically different devices may be lowered, if CO2 reduction takes place simultaneously with water splitting in the very same device. However, in contrast to water splitting, the Faraday efficiency of electro-chemical CO2 reduction towards the sought end product, e.g., methanol, is much smaller than one. In this talk, I will review some renown facts most importantly the one that almost all “electro-chemical” CO2 reduction reactions in aqueous media are strictly speaking catalytic reactions taking place in parallel to electro-chemical water splitting. Based on this we arrive at a new interpretation of the observed voltage-current relations. I will present some fundamental experiments corroborating this interpretation and its consequences for new materials design for both catalytic as well as electro-chemical CO2 reduction.
The seminar can also be followed remotely by joining the online Cisco WebEx meeting (connection possible 15 minutes before the talk).
See here the documentation how to install the Cisco WebEx add-on on your computer.
In case of problem, you can contact our IT support (37679 - [email protected] )
State-of-the-art production of renewable hydrocarbons may be divided into three steps: light harvesting and conversion to electricity (photovoltaics), water electrolysis, and conversion of the hydrogen to hydrocarbons by catalytic reaction with CO2. Electrolysis is an electro-chemical process taking place at two spatially separated electrodes. The Faraday efficiency for water electrolysis is near one; the voltage–current relation is thus sufficient to characterize the water-splitting reaction and defines the overall efficiency, which reaches more than 80% in modern electrolyzers. The efficiency of the subsequent step, the catalytic reaction of hydrogen with CO2 to produce hydrocarbons, depends on thermodynamic factors (Gibbs free energy) and kinetic constraints requiring elaborated temperature/pressure and additional separation and/or cycling procedures. The effort of the required various technically different devices may be lowered, if CO2 reduction takes place simultaneously with water splitting in the very same device. However, in contrast to water splitting, the Faraday efficiency of electro-chemical CO2 reduction towards the sought end product, e.g., methanol, is much smaller than one. In this talk, I will review some renown facts most importantly the one that almost all “electro-chemical” CO2 reduction reactions in aqueous media are strictly speaking catalytic reactions taking place in parallel to electro-chemical water splitting. Based on this we arrive at a new interpretation of the observed voltage-current relations. I will present some fundamental experiments corroborating this interpretation and its consequences for new materials design for both catalytic as well as electro-chemical CO2 reduction.
The seminar can also be followed remotely by joining the online Cisco WebEx meeting (connection possible 15 minutes before the talk).
See here the documentation how to install the Cisco WebEx add-on on your computer.
In case of problem, you can contact our IT support (37679 - [email protected] )
Practical information
- General public
- Free