Imec, the leading research and innovation hub in nanoelectronics, energy and digital technology, within the partnership of EnergyVille, announced a record result for its 4-terminal perovskite/silicon tandem photovoltaic cell. In fact, with a reported power conversion efficiency of 27.1%, the new tandem cell tops the most efficient standalone silicon solar cell. Further careful engineering of the Perovskite material will bring efficiencies over 30% in reach.

Imec’s new record tandem cell uses a 0.13 cm² spin-coated perovskite cell developed within the Solliance cooperation, stacked on top of a 4 cm² industrial interdigitated back-contact (IBC) silicon cell in a 4-terminal configuration, which is known to have a higher annual energy yield compared to a 2-terminal configuration. Additionally, scaling up the tandem device by using a 4 cm² perovskite module on a 4 cm² IBC silicon cell, a tandem efficiency of 25.3% was achieved, surpassing the stand-alone efficiency of the silicon cell.

Researchers at the University of Washington report that a prototype perovskite thin-film has performed even better than today’s best solar cell materials at emitting light. “It may sound odd since solar cells absorb light and turn it into electricity, but the best solar cell materials are also great at emitting light,” said co-author and UW chemical engineering professor Hugh Hillhouse. “In fact, typically the more efficiently they emit light, the more voltage they generate.”

a back-reflector A back-reflector surface used to test perovskite performance. Each quadrant is a different surface material — gold, titanium, palladium or a silica compound — upon which the perovskite material would be deposited for experiments

The UW team achieved a record performance using a lead-halide perovskite, by chemically treating it through a process known as “surface passivation,” which treats imperfections and reduces the likelihood that the absorbed photons will end up wasted rather than converted to useful energy.