It's often smarter to borrow from nature than reinvent the wheel. That was the approach of researchers at the University of Illinois at Chicago (UIC) to remove carbon dioxide (CO2) from the atmosphere, and convert it into an efficient, inexpensive fuel. The result: an artificial leaf that turns CO2 into fuel, at a cost comparable to a gallon of gasoline" could render fossil fuel obsolete, according to the researchers. The "leaf" is one of a growing number of inventions that mimic photosynthesis to remove excess carbon from the atmosphere, and convert it into new, sustainable forms of energy to power our world. "The new solar cell is not photovoltaic - it's photosynthetic," said [the study's lead author] Amin Salehi-Khojin. "Instead of producing energy in an unsustainable one-way route from fossil fuels to greenhouse gas, we can now reverse the process and recycle atmospheric carbon into fuel using sunlight." The concept of reduction reaction - converting CO2 into a burnable form of carbon - isn't new. But scientists previously relied on silver and other expensive precious metals to break gas into storable energy. UIC researchers took a different approach. When light strikes the "leaf," hydrogen and carbon monoxide bubble from the cathode, while free oxygen and hydrogen ions are released from the anode. Leafs could be spread throughout a solar farm, or used in smaller applications, the researchers said.