Last month at the meeting of the Japan Society of Applied Physics, a research group from the Kyoto Institute of Technology introduced a new photovoltaic cell that is capable of generating electricity not only from visible light, but from ultraviolet and infrared light as well. The research group, led by associate professor Saki Sonoda, hopes that this will lead to a more efficient PV cell that can be single-junction rather than the more conventional multi-junction.
These new PV cells were made by 'doping' a wide bandgap transparent composite semiconductor -- in this case, gallium nitride (GaN) -- with a 3d transition metal such as manganese. For the atomically impaired among us, the other metals of that family would be scandium, titanium, vanadium, chrome, iron, cobalt, nickel, copper, and zinc.
So, just what is a multi-junction PV cell? With a multi-junction PV cell, multiple thin films of varying absorption capabilities are required to catch the entire spectrum of light. But with a cell such as the prototype put forward by this research group, all that light can be absorbed using a single junction cell.
With such advancements in the field of photovoltaics it's exciting to see that the much hyped potential of thin film solar is not only coming to fruition, but it can also get even better still. Add to this the recent news that carbon sheets might possibly be used in solar panels, and the future looks bright for the industry indeed.