Green Transition

From CO2 to green chemicals—researchers are one step closer

An international research team at DTU has increased the shelf life of electrolyzers that convert CO2 from half a day to 100 hours. This is good news for companies working with the process. The findings were recently published in Nature Catalysis.

 Postdoc Qiucheng Xu from DTU is setting up and installing a reactor to analyze X-ray rays. The method makes it possible to monitor changes on the electrolytes during electrolysis of CO2. Photo: Bjørt Oladottir Joensen


Electrolysis with CO2 is a process in which carbon dioxide (CO2) is decomposed using electricity. This process has the potential to contribute to CO2 reduction and the production of useful products such as hydrogen (H2) and carbon monoxide (CO) that can be used as fuels or in chemical processes. Here follows a basic explanation of CO2 electrolysis:

Electrolyte cell: The process requires an electrolyte cell in which CO2 is present as gas or dissolved in a liquid, such as water (H2O). The electrolyte cell contains an anode and a cathode, as well as an electrolyte.

Anode and cathode: The anode is the positive electrode, and the cathode is the negative electrode. They are made of materials that can conduct electricity and withstand corrosion. Typically, materials such as platinum or graphite foam are used.

Electric power source: An external power source, such as a battery or power supply, connects to the anode and cathode to create an electrical circuit.

Electrochemical reaction: When an electric current runs through the electrolyte, an electrochemical reaction occurs at the anode and cathode. At the anode, CO2 molecules are oxidized to carbonate ions (CO3^2-) or carbonic acid (H2CO3), depending on the conditions. At the cathode, water (H2O) is reduced to hydrogen (H2) and possibly also to carbon monoxide (CO), depending on the process.



The research was funded by Horizon Europe - European Commission, VILLUM FONDEN & VELUX FONDEN, and the Innovation Fund Denmark. The research was conducted in collaboration with European Synchrotron Radiation Facility (ESRF) Jakub Drnec.