What if you could come up with a way to generate energy and efficiently use carbon dioxide—greenhouse gas—in the process? Stuart Licht
, a GW chemist based at the University’s Institute of Basic Energy Science and Technology in Ashburn, Va., has created a method that uses sunlight to electrochemically synthesize molecules in order to generate chemicals used for manufacturing everything from plastic to pharmaceuticals.
That method, called the Solar Thermal Electrochemical Photo (STEP) process, could eventually use the energy generated from splitting carbon dioxide molecules collected from the atmosphere. And unlike other manufacturing processes, STEP does not produce carbon dioxide.
Finding a way to reduce harmful carbon emissions and generate useful chemicals and fuels at the same time has great appeal for Licht, whose prior research has focused on many aspects of renewable energy.
“We’d like to create a CO2
generating-free society,” he said, noting that current methods of disposing of carbon dioxide involving burying it as a gas or compound.
Licht’s process would allow carbon dioxide to be reused by converting it to carbon-containing compounds. However, carbon dioxide is a stable material and had been difficult to convert without using a high amount of energy.
The STEP process is more efficient than current photovoltaics that collect sunlight for energy, according to Licht. Unlike traditional solar energy, STEP uses the entire spectral range including the ultraviolet and infrared bands. The sunlight is magnified with mirrors, reflectors or lenses and used at 500 to 1,000 times the usual intensity. During the procedure, the sunlight is split and the infrared bands heat chemical reactants. That decreases the voltage needed to electrolyze them to useful products.
“We direct all excess solar heat to the processes to allow us to form these chemicals at solar energy conversion efficiencies previously thought to be impossible,” explained Licht.
Licht is also working on higher storage cathodes for batteries, as well as boride air fuel cells with energy storage capacities comparable to that provided by traditional gasoline.