A work led by researchers from CINE and RCGI advances the knowledge about the techniques that are capable of elucidating the carbon dioxide reduction reaction (CO2 RR) – a process that transforms this greenhouse gas into compounds of industrial utility and high added value.

The study contributes to developing solutions that reduce carbon dioxide emissions to the atmosphere and, at the same time, take advantage of carbon dioxide as a raw material, replacing petroleum derivatives and other compounds. CINE and RCGI are research centers founded and financed by the São Paulo Research Foundation (FAPESP) and Shell to carry out research on new energies and greenhouse gases, respectively. Both centers have among their research topics the reduction of carbon dioxide.

As a result of this work, a review article has just been published in the scientific journal ChemElectroChem, highlighted on the cover. The review addresses the evolution, over time, of devices developed for the study of CO2 RR. In this reaction, the carbon dioxide molecule is reduced (gains electrons) and transforms into compounds such as ethylene, ethanol, formic acid or methanol. The process is promising to enable the recycling of CO2, but its efficiency still needs to be improved. And, for this, it is necessary to better understand the complex mechanism of the reaction, especially with regard to the formation of final compounds (called “products”) and intermediates (those that are formed during the process).

The ChemElectroChem review article focuses on adaptations that have already been made in electrochemical cells (the devices where reactions take place) to integrate the technique of mass spectrometry, which identifies chemical compounds. Among other aspects, the authors address one of the main challenges in the application of this technique to CO2 reduction: the identification and quantification in real time of the intermediates and products formed, even under intense bubble generation on the electrode surface. “These reactions form many bubbles because the reduction of CO2 occurs together with the release of hydrogen (H2) in the same potential range”, explains Professor Raphael Nagao (UNICAMP), researcher of the Dense Energy Carriers division at CINE and corresponding author of the review with Professor Fabio H. B. Lima (IQSC-USP), who is a member of RCGI. “In the review, we show how advanced setups can overcome this problem, in addition to measuring the mass/load signals of the species with the applied potential with good synchronization”, adds Nagao.

The study was carried out with funding from FAPESP, Shell, FAPEMA, CNPq and Capes, in addition to the support of ANP.

Paper reference: Electrochemical Mass Spectrometry: Evolution of the Cell Setup for On-Line Investigation of Products and Screening of Electrocatalysts for Carbon Dioxide Reduction. Adriana C. Queiroz, Maykon L. Souza, Mariana R. Camilo, Wanderson O. Silva, Daniel A. Cantane, Igor Messias, Maria R. Pinto, Raphael Nagao, Fabio H. B. Lima. ChemElectroChem. https://doi.org/10.1002/celc.202101408