NREL study shows nanotube semiconductors improve PV system efficiency

The National Renewable Energy Laboratory (NREL) announced the results of a study on Monday that found single-walled carbon nanotube semiconductors potentially increase efficiency of photovoltaic solar systems by requiring less energy to convert sunlight to electricity.

The NREL study was built upon the Nobel Prize-winning work of Rudolph Marcus. Marcus discovered the rate at which an electron moves from one chemical to another. NREL researchers used this information to observe the photo-induced electron transfer for single-walled carbon nanotubes (SWCNT), an organic semiconductor that is increasing in popularity. The researchers wanted to determine if SWCNT could offer increased efficiency in organic PV systems.

“What we find in our study in this particular system – nanotubes with fullerenes – have an exceptionally low reorganization energy and the nanotubes themselves probably have very, very low reorganization energy,” NREL senior scientist and study co-author Jeffrey Blackburn said.

The study found that SWCNT served as a donor to an electron in organic PV systems. If further developed, the technology could optimize energy efficiency of PV solar infrastructure and systems.

The paper, titled, “Tuning the driving force for exciton dissociation in a single-walled carbon nanotube heterojunctions,” appeared in the new issue of Nature Chemistry.