Emerging e-fuel technologies often use water-gas repulsive reactivation (RWGS) to convert atmospheric CO2 to CO. Although effective, this reaction requires high temperature and complex gas separation for high performance. However, for the first time in the world, scientists from Japan have now proven high CO2 conversion rates at very low temperatures in a chemically modified version of RWGS using novel copper-indium oxide.
With climate change worsening, there is a need for technologies capable of capturing and using the CO’s atmosphere.2 (carbon dioxide) and reduce our carbon footprint. Interior of renewable energy, CO2E-fuel based has emerged as a promising technology that seeks to convert atmospheric CO2 into clean fuel. The process involves the production of synthetic gas or syngas (a mixture of hydrogen and carbon monoxide (CO)). With the assistance of the water-gas transfer reorganization (RWGS), CO2 broken down to the CO required for syngas. While promising in terms of conversion efficiency, the RWGS response calls for high temperatures (> 700 ° C) to prevail, while at the same time generating unwanted byproducts.
To address these problems, scientists developed a chemically modified volatile version of the CO-modified RWGS reaction2 to CO in a two-step mode. First, metal oxide, used as an oxygen storage material, is depleted by hydrogen. After that, it is re-oxidized by CO2, extracting CO. This method is free of undesirable byproducts, simplifies gas separation, and can be enabled at lower temperatures depending on the selected oxide. As a result, scientists have been looking for oxide products that exhibit high levels of oxidation reduction without the need for high temperatures.
In a recent study published in Chemical Science, scientists from Waseda University and ENEOS Corporation in Japan have revealed that the novel indium oxide was modified with copper (Cu – In2O.3) exhibits modern CO2 conversion rate of 10 mmolh-1g-1 at very moderate temperatures (400-500 ° C), making it a disadvantage among oxygen storage materials required for CO at low temperatures2 turn. To better understand this behavior, the team studied the structural properties of Cu-In oxide along with the kinetics involved in the chemical reaction of RWGS.
The scientists performed X-ray-based analyzes and found that the sample initially contained parental material, Cu2In2O.5, which was initially reduced by hydrogen to form a Cu-In alloy and indium oxide (In2O.3) and then oxidized by CO2 to the result of Cu – In2O.3 and X-ray data showed CO. that it was oxidized and reduced during the reaction, giving the main news to scientists. “The X-ray measurements made it clear that the chemically curved RWGS reaction is based on the reduction and oxidation of Indium which leads to the formation and oxidation of the Cu-In alloy,” says Professor Yasushi Sekine of University Waseda, who led the study.
The genetic studies provided further insight into the reaction. The reduction step showed that Cu was responsible for the reduction of indium oxide at low temperature, while the oxidation step showed that the surface of Cu-In alloy maintained a highly reduced state while its mostly oxidation. This allowed the oxidation to occur twice as fast as other oxygen. The team attributed this strange oxidation behavior to the rapid migration of negatively charged oxygen ions from the surface of a Cu-In alloy to its bulk, which helped to produce a selective mass of oxide.
The results, as expected, have inspired scientists about the future prospects for copper-indium oxygen. “Given the current situation with carbon emissions and global warming, a high-performance carbon dioxide conversion process is highly desirable. While reacting RWGS with a chemical loop works to good with many oxides, our novel Cu-In-oxide here shows significantly higher performance than any of them.We hope this will make a significant contribution to reducing our carbon footprint and increasing our carbon footprint. driving man towards a more sustainable future, “Sekine concluded.
Story source:
Materials provided by Waseda University. Note: Content can be edited for style and length.