The researchers, from the University of Cambridge, have previously shown that biological catalysts, or enzymes, can produce fuels cleanly using renewable energy sources, but at low efficiency.
Their latest research has improved fuel production efficiency by 18 times in a laboratory setting, demonstrating that polluting carbon emissions can be turned into green fuels efficiently without any wasted energy. The results are reported in two related papers in Nature Chemistry and Proceedings of the National Academy of Sciences.
Most methods for converting CO2 into fuel also produce unwanted by-products such as hydrogen. Scientists can alter the chemical conditions to minimise hydrogen production, but this also reduces the performance for CO2 conversion: so cleaner fuel can be produced, but at the cost of efficiency.
The Cambridge-developed proof of concept relies on enzymes isolated from bacteria to power the chemical reactions which convert CO2 into fuel, a process called electrolysis. Enzymes are more efficient than other catalysts, such as gold, but they are highly sensitive to their local chemical environment. If the local environment isn’t exactly right, the enzymes fall apart and the chemical reactions are slow.
The Cambridge researchers, working with a team from the Universidade Nova de Lisboa in Portugal, have developed a method to improve the efficiency of electrolysis by fine-tuning the solution conditions to alter the local environment of the enzymes.
Read more at: University of Cambridge