It is said that standard polysilicon photovoltaic cells do not quite cut the mustard any more these days, as they do not respond as well to the whole spectrum of sunlight. This in turn would limit the amount of photons which they are able to convert into electricity. The same group of scientists also mentioned that standard polysilicon comes with a theoretical maximum efficiency of 33.7%, where the kind of nanotube technology which is present and tested could eventually surpass that limit.
The combination of carbon nanotubes, hollow cylinders with walls that measure a mere one-atom thick (or rather, should we say, thin?), alongside photonic crystals end up with an “absorber-emitter.” Whenever the nanotubes absorb concentrated sunlight, their temperature would rise, ending up heating the device to as much as 962 degrees Celsius (1,763 degrees Fahrenheit). These heated crystals then emit light which the photovoltaic cell could then absorb and transform into electricity – nifty!