Battery That Could Be Recharged With Carbon Dioxide Developed
The scientists have developed a battery that can be recharged with a water-based solution that has dissolved carbon dioxide (CO2). This CO2 is discharged from fossil fuel power plants.
The discovery was described in the recent issue of Environmental Science & Technology Letters. It was led by Taeyong Kim, Christopher A. Gorski and Bruce E. Logan at Pennsylvania State University. Gorski told Phys.org that this discovery offers an alternative, simpler means to capturing energy from CO2 emissions compared to existing technologies that require expensive catalyst materials and very high temperatures to convert CO2 into useful fuels.
— Sébastien Raymond (@raymondsebas) February 9, 2017
So, how does this work? The scientists dissolved the CO2 gas and ambient air in separate containers with an aqueous solution, in a method known as sparging. Once this method is done, the CO2 solution produces bicarbonate ions that provide a lower pH of 7.7. Then, the team injected each solution into one of the two channels in a flow cell that creates a pH gradient in the cell.
This flow cell contains electrodes on opposite sides of the two channels and the semi-porous membrane between the two channels that inhibits the instant mixing while still allowing ions to pass through. The different ions pass through the membrane because of the pH difference between the two solutions. This then generates the voltage difference between two electrodes and that caused the electrons to flow along a wire connecting the electrodes.
Once the flow cell is discharged, it can be recharged again trough switching the channels that the solutions flow into. The charging mechanism then is reversed and the electrons flow in the opposite direction. This cell could maintain its performance for more than 50 cycles of alternating solutions.
Carbon dioxide (CO2) is a chemical compound that is a colorless and odorless gas. It is essential to life on the planet Earth. CO2 is made up of a carbon atom covalently double bonded to two oxygen atoms. It exists in the atmosphere of Earth at about 0.04 percent (400 ppm) concentration, natural gas and petroleum. Other natural sources of carbon dioxide are hot springs, volcanoes, geysers and carbonate rocks. It is soluble in water and may be found in rivers, groundwater, lakes, ice caps, seawater and glaciers, too.