Presence of surplus carbon dioxide in the atmosphere has taken center stage in the environmental science. All over the world people are worried about the excess amount of carbon dioxide in the atmosphere because it’s causing undesirable changes in the surroundings such as green house effect, global warming, melting of ice caps on the glaciers etc. So most of the environmental scientists are trying to minimize the amount of atmospheric carbon dioxide.
Researchers at Pennsylvania State University are working towards the same goal with the help of sunlight and titanium oxide nanotubes. These two elements, sunlight and titanium oxide nanotubes can transform carbon dioxide into methane. Methane can be utilized as energy source. It seems like double benefit. At one hand, we are reducing the quantity of carbon dioxide into the atmosphere and we would be less dependent on fossil fuels.
Craig Grimes of Pennsylvania State University is working on this project with Oomman Varghese, Maggie Paulose and Thomas LaTempa. Craig Grimes shares his views, “Right now there is lots of talk about burying carbon dioxide, which is ridiculous. Instead we can collect the waste out of the smoke stack, put it though a converter, and presto, use sunlight to change [CO2] back into fuel.”
The team of researchers arranged the nanotubes vertically somewhat on the lines of empty honeycomb. The top of the nanotubes is covered with a thin, reddish-brown layer of copper oxide. Here the copper and titanium oxide operate as catalysts. They increase the pace of chemical reactions that happen naturally.
How does the whole process work? When sunlight strikes the copper oxide, carbon dioxide is transformed into carbon monoxide. When sunlight comes into contact with titanium oxide, water molecules split apart. In this reaction hydrogen is freed from the water and the carbon released from CO2 , unite again to create burnable methane. Here oxygen is released as byproduct. If we adjoin more carbon dioxide and sunlight, we will obtain more methane. Craig Grimes calculates that focusing the light collected from 1,100 square feet onto one of the membranes would generate more than 132 gallons of methane on a sunny day. Grimes is of the opinion that formation of methane by this process is the solar power by another name. Instead of storing electrons in batteries, Grimes’ initiative would store energy chemically.
We can use the methane in many ways. In cooking gas cylinders, we can utilize methane instead of propane. Coal-burning power plants could utilize the methane to heat water and generate more electricity. Kyoung-Shin Choi, a chemistry professor at Purdue University, points out another important benefit of the methane. He says we don’t have to invest money in infrastructure as it already exists. “If you want to use hydrogen as a energy source in the future, you have to convert all the existing infrastructure,” said Choi. “But we’ve been using methane for years, and can utilize all the infrastructure we already have.”
“It’s a clean and sustainable cycle as long as you have sun and water,” said Choi.
But we have to wait for its commercial use. Only future can provide an answer to us regarding this.