New technology aims to efficiently transform sunlight into energy-storing compounds
When it comes to converting renewable resources into clean energy, there’s no better model to follow than that of plants. “Plants use the natural process of photosynthesis to turn solar energy, water and carbon dioxide into fuel,” says Antoni Llobet, professor and group leader at the Institute of Chemical Research of Catalonia (ICIQ-CERCA). Drawing inspiration from this natural process, researchers have developed artificial photosynthetic systems such as the photoelectrochemical cell (PEC), which can convert solar energy into electricity. This electricity can then be used to, for example, charge the battery of an electric vehicle. Unfortunately, PEC technology has its drawbacks, including not being nearly as efficient at absorbing sunlight as plants are. The EU-funded LICROX project addressed this problem and made an effort to help PECs become an efficient, cost-effective technology for the direct conversion of solar energy. “Our goal was to develop and test a PEC for converting sunlight into carbon molecules capable of storing chemical energy,” adds Llobet, who served as the project’s scientific coordinator.
Obtaining carbon-based products such as ethylene
The LICROX PEC is unique in that it incorporates light-trapping mechanisms that can boost light-harvesting efficiency and catalysis. “Using only abundant elements, these mechanisms can selectively drive water oxidation and carbon dioxide reduction reactions,” explains Llobet. “In doing so, the PEC is able to efficiently obtain carbon-based products such as ethylene, which is one of the most important products currently used by the chemical industry.”
Transforming light and CO2 into energy-storing compounds
According to Llobet, the project succeeded at demonstrating the potential for transforming light and CO2 into chemical energy-storing compounds. Specifically, he highlights the project’s success at completing a final coupling of a photoanode and organic photovoltaic cell with a dark cathode – a coupling that showed selectivity towards ethylene production. “In this regard, the use of new tandem catalysts combining copper nanoparticles with molecular catalysts allowed us to increase ethylene selectivity,” notes Llobet. Researchers are currently carrying out final lab tests and putting the finishing touches on a pre-industrial prototype that will be used to upscale and optimise some of the project’s results.
Driving the transition from fossil fuels to solar energy
The project also produced a life cycle assessment of the LICROX PEC. Furthermore, researchers, working together with stakeholders, conducted a large-scale survey of citizens from across Europe to assess and identify any societal concerns relating to emerging energy technologies. “LICROX was a highly multidisciplinary effort where chemistry, physics, engineering, optics and social involvement specialists joined together with the shared aim of contributing new innovative solutions for the global transition from fossil fuels to solar energy,” concludes Llobet.
Keywords
LICROX, plants, CO2, photosynthesis, solar energy, fuel, fossil fuels, renewable resources, clean energy, photoelectrochemical cell, PEC, ethylene
