Controlled placement of carbon nanotubes in nanostructures could result in a huge boost in electronic performance in photovoltaic solar cells, researchers at Umeå University in Sweden have discovered. However, the projects have found that the nanotubes are difficult to form into well-ordered networks; they tend to be randomly arranged.
In the new study, published in Advanced Materials, the researchers were able to engineer the nanotubes into complex network architectures with controlled nanoscale dimensions inside a polymer matrix. That structure allows for better conductivity (lower loss of power) and reduction of the number of high-cost nanotubes needed.
“We have found that the resulting nano networks possess exceptional ability to transport charges, up to 100 million times higher than previously measured carbon nanotube random networks produced by conventional methods,” says David Barbero, project leader and assistant professor at the Department of Physics at Umeå University.
“This innovation has direct implications for the next generation of carbon-based solar cells, which use carbon nanotubes and other carbon materials (graphene, semi-conducting polymers, etc.) That’s because the new nano-engineered networks show much increased charge transport compared to commonly used networks today. These new nano-networks could also in principle be advantageously used in any nanocomposite material where efficient charge transport is required, and where low amounts of nanotubes are necessary.
“This new architecture enables a higher degree of interconnection between nanotubes and more robust charge transport pathways in the device,” he explained. “This is expected to increase device efficiency, but also to reduce materials costs because at least 100 times less nanotubes are necessary to form efficient charge transport networks.”