13 September 2011

By Kari Williamson

The carbon nanotubes are rolled up sheets of honeycomb-structured carbon atoms that are typically 1 nm in diameter.

The single or multi-walled carbon nanotube structures have better conductivity than other known single element material including copper. The thermal conductivity is better than diamond, and it has mechanical strength surpassing that of high tensile steel.

The University's Advanced Technology Institute (ATI) has found a way to enhance the photo-current of organic materials based solar PV cells using these multi-wall carbon nanotubes.

The work has the potential to develop low cost, light-weight, printable and flexible solar PV cells.

Incorporating nanotubes into an ultra-thin charge donor-acceptor organic material blend helps to improve photo-generated charge transfer from the solar PV cell to the electrical circuit.

Professor Ravi Silva, Director of the ATI says the incorporation of carbon nanotubes into the traditional organic solar PV cell structure in the form of triple junctions allows for more charges to be extracted from the cell, increasing the power delivery to the load.

"The main obstacle for this approach has been the deleterious effects associated with incorporating the nanotubes. We have adopted a method to alter the outer tube of the multi-wall nanotube so that they can be mixed well in organic materials with suitable solvents," he explains.

Lead researcher Dr Damitha Adikaari adds: "The approach is adaptable to a large number of similar systems, which would allow for better design freedom of large area, printable and flexible solar cells leading to lower cost."

The research is fully sponsored by E.ON.