This device uses red light to generate electricity. It has two parts: a blue photocathode and a green photoanode, separated by a special membrane. A bacterium (S. ovata) helps convert carbon dioxide, while a platinum-gold mix assists with another reaction. Illustration courtesy of Peidong Yang
Recently, a handful of “climate innovators” were identified as a part of Berkeley’s ecosystem of innovation and entrepreneurship to combat climate change. Among them was Peidong Yang, a professor of chemistry and of materials science and engineering.
Yang is creating biohybrid systems that mimic the natural process of photosynthesis, absorbing sunlight and carbon dioxide (CO₂) to provide clean and renewable liquid fuel. Because sunlight isn’t always available, his team is identifying ways to store renewable energy into chemical bonds. One idea is to use sunlight to create chemical fuels that can be stored and used later. This process, known as photoelectrochemical CO₂ reduction, could help us store energy and reduce carbon emissions.
Today his team has taken a first step by looking at ways to achieve carbon neutrality. We know that carbon neutrality would not only avoid the worst consequences of climate change - it also brings benefits to communities and society as a whole including less pollution, health improvements, and the creation of green jobs.
But breaking down CO₂ - removing harmful chemicals - can be tricky because it has such strong bonds. While humans have created many catalysts to help with this, nature’s methods, developed over millions of years, are still the most effective.
One such “natural” system combines bacteria with silicon nanowires. When red light hits the silicon nanowires, it produces electrons that help the bacteria, *Sporomusa ovata*, convert CO₂ into a substance called acetate.
His team designed a special device that uses a combination of a photocathode and a photoanode. This device only needs low-intensity red light (much weaker than normal sunlight) to work, making it functional even in low-light conditions like in the winter or during early morning and late evening. This setup allows the device to continuously convert CO₂ into useful chemicals, day and night. His findings have been published in Nature Catalysis
This innovation could help reduce CO₂ emissions and produce valuable chemicals for a sustainable future.