Researchers have created new molecules that can efficiently capture substantial amounts of carbon dioxide from the atmosphere, a crucial step in fighting climate change.
Oregon State University researchers have developed innovative molecules capable of swiftly capturing large quantities of carbon dioxide from the air, which is a key strategy for addressing climate issues.
The research, which concentrated on titanium peroxides, builds upon previous work examining vanadium peroxides. This study is part of a significant federal initiative aimed at developing novel techniques and materials for direct air capture (DAC) of carbon dioxide, which is released through fossil fuel combustion.
The results of the study, spearheaded by May Nyman and Karlie Bach from OSU’s College of Science, were published today in Chemistry of Materials.
In 2021, Nyman, who serves as the Terence Bradshaw Chemistry Professor, was appointed to lead one of nine DAC projects supported by the Department of Energy, which received an initial funding boost of $24 million. Her team is investigating how certain transition metal complexes interact with air to extract carbon dioxide and transform it into a metal carbonate, akin to those found in a variety of natural minerals.
Transition metals, which are positioned close to the center of the periodic table, derive their name from the shifting of electrons between low and high energy states, resulting in unique colors.
While facilities designed to filter carbon dioxide from the atmosphere are still in their early stages, technologies that address carbon dioxide release at the source, such as at power plants, have matured considerably. Experts believe that both approaches to carbon capture will be essential to mitigate the severe impacts of climate change.
Currently, there are 18 operational direct air capture plants in the United States, Canada, and Europe, with plans for an additional 130 globally. However, the process of direct air capture faces challenges such as high costs and substantial energy demands compared to treatment of industrial emissions. The relatively low atmospheric concentration of carbon dioxide, at four parts per million, also complicates the effectiveness of capture materials.
“We decided to explore titanium as it is 100 times less expensive than vanadium, more plentiful, eco-friendlier, and already widely used in industry,” explained Bach, a graduate student working in Nyman’s lab. “Additionally, it is positioned right next to vanadium in the periodic table, leading us to hypothesize that its carbon capture characteristics might be sufficiently similar to vanadium’s to make it effective.”
Bach, Nyman, and their team succeeded in creating various new tetraperoxo titanate structures — a configuration that features a titanium atom bonded with four peroxide groups — which displayed different capabilities in removing carbon dioxide from the atmosphere. These tetraperoxo formations tend to be very reactive due to the energetic nature of the peroxide groups.
Related peroxotitanates have attracted interest for potential applications in catalysis, environmental chemistry, and materials science. However, the tetraperoxotitanates discussed in this research had not been successfully synthesized before; Bach managed to achieve this using affordable materials to facilitate high-yield reactions.
“Our favorite carbon capture structure we identified is potassium tetraperoxo titanate, which is particularly interesting because it also functions as a peroxosolvate,” Bach stated. “This means, in addition to having peroxide links with titanium, it incorporates hydrogen peroxide into its structure, which we think contributes to its high reactivity.”
The research indicated that the carbon capture capacity of potassium tetraperoxo titanate was approximately 8.5 millimoles of carbon dioxide per gram, nearly double that of vanadium peroxide.
Named after the titans from Greek mythology, titanium is as durable as steel yet considerably lighter. It is non-toxic, resistant to corrosion, and ranks as the ninth most abundant element found in the Earth’s crust, appearing in various natural sources including rocks, soil, and even in trace amounts in the human body.
Other contributors from Oregon State on this publication included assistant professors Tim Zuehlsdorff and Konstantinos Goulas, postdoc Eduard Garrido Ribó, graduate students Jacob Hirschi, Zhiwei Mao, and Makenzie Nord, as well as Lev Zakharov, a crystallographer and interim manager of OSU’s X-Ray Diffraction Facility.
This research was also supported by an instrument grant from the Murdock Charitable Trust.
