Language
Country/Area
No result found
Mysterious Catalysts: Why can copper make a variety of carbon compounds, but zinc can't?
In the context of today's discussion of sustainable energy development, the electrochemical reduction of carbon dioxide (CO2RR) has received increasing attention. This technology not only converts carbon dioxide into a variety of chemicals, but also helps reduce greenhouse gas emissions. However, among many catalysts, why can copper effectively produce different carbon compounds, while zinc is unable to do so?
Any technological progress is inseparable from the selection and application of catalysts. Differences in catalysts will directly affect the efficiency of the reaction and the types of products obtained.
CO2RR uses electrical energy to convert carbon dioxide into more reducing chemicals. Its products include formic acid (HCOO-), carbon monoxide (CO), methane (CH4), ethylene (C2H4) and ethanol (C2H5OH). Technical challenges to this process include high electricity costs and the fact that carbon dioxide often contains impurities that must be purified before reduction. The first CO2 reduction experiments in the 19th century used zinc as a cathode to reduce carbon dioxide to carbon monoxide, and subsequent research increased dramatically in the 1980s, especially after the oil embargo of the 1970s.
Currently, many companies are developing electrochemical reduction technology for carbon dioxide, including Siemens, Dioxide Materials, Twelve and GIGKarasek. Although there is no room-temperature electrolyzer that can be commercialized yet, high-temperature solid oxide electrolyzers (SOECs) have been launched by many companies and have achieved success in the process of CO2 reduction of carbon monoxide.
The commercial viability of high-temperature solid oxide electrolyzers has demonstrated the production of 6-8 kWh per cubic meter of CO with a purity of 99.999%.
In the electrochemical reduction process of CO2, the role of catalyst is crucial. Although many metal catalysts do not show ideal results in catalyzing the reduction of carbon dioxide, most prefer to promote the generation of hydrogen. Catalysts can be divided into different categories based on the product. These include selective catalysts such as tin or bismuth that promote the production of formic acid, silver or gold that focus on the production of carbon monoxide, and copper catalysts that can produce a variety of reduction products. , such as methane, ethylene and ethanol.
Copper catalysts are unique in their ability to generate multi-carbon compounds from carbon dioxide, including ethylene, ethanol and other higher-order products.
However, although zinc catalyst performed well in early experiments, its application has gradually been restricted with the advancement of science and the development of technology. The fundamental reason is that zinc is prone to side reactions during the reduction process, resulting in low product selectivity. At the same time, zinc does not have the ability to form metal carbonate complexes similar to copper, which greatly weakens its potential in effectively catalyzing multi-carbon compounds.
In order to further understand this phenomenon, we can note that in the CO2RR process, the selectivity and efficiency of the catalyst are often affected by many factors, including the performance of the catalyst, the composition of the electrolyte and the conditions of the reaction process. Researchers are working to optimize these factors, improve the overall efficiency of CO2 reduction, and find new catalysts to replace zinc to increase the richness of the product.
In this constantly evolving field of scientific research, catalyst innovation and technological breakthroughs will greatly affect the sustainable production of various chemicals, thus promoting the dual realization of environmental protection and economic benefits.
It is undeniable that the catalytic potential of copper provides us with a bright future in the process of exploring CO2 conversion. However, by in-depth study of catalyst selectivity, can we unveil the mystery of more catalysts and let The re-emergence of metals such as zinc that were originally unable to participate?
