Strano’s team is the first to construct nanotube fibers in which the properties of different layers can be controlled — an achievement made possible by recent advances in separating nanotubes with different properties. It is not just the higher rate of concentrated energy that makes the solar funnels a breakthrough — by utilizing carbon nanotubes, solar cells can be constructed at a lower-cost than traditional silicon-based solar cells.
While the cost of carbon nanotubes was once prohibitive, it has come down in recent years as chemical companies build up their manufacturing capacity. “At some point in the near future, carbon nanotubes will likely be sold for pennies per pound, as polymers are sold,” says Strano. “With this cost, the addition to a solar cell might be negligible compared to the fabrication and raw material cost of the cell itself, just as coatings and polymer components are small parts of the cost of a photovoltaic cell.”
In theory, with this new technology, not only could the solar funnels be used to generate power, but they could be used in applications where light needs to be concentrated — such as telescopes or night-vision goggles. The design behind the solar funnel is quite innovative, by capturing the light in a tube, Strano’s solar funnel, also know as an nanotube antenna, boosts the number of photons that can be transformed into energy, but in a similar process to that of tradition solar cells.
Strano’s team is now reportedly working on ways to minimize the energy lost as excitons flow through the fiber, as well as new antennas that would lose only 1 percent of the energy they absorb versus the standard 13 percent.