E-Mail Australian photovoltaics researchers have made a 'cool' discovery: Singlet fission and tandem solar cells - two innovative ways to generate solar power more efficiently - also help to lower operating temperatures and keep devices running for longer. Tandem cells can be made from a combination of silicon - the most commonly used photovoltaics material - and new compounds like perovskite nanocrystals, which can have a larger bandgap than silicon and help the device to capture more of the solar spectrum for energy generation. Singlet fission, meanwhile, is a technique that produces twice the electronic charge carriers than normal for each photon of light that's absorbed. Tetracene is used in these devices to transfer the energy generated by singlet fission into silicon.