A research team at KTH Royal Institute of Technology has developed a synthetic alloy that increases perovskite cells' durability while preserving energy conversion performance.
'Perovskite usually dissolves immediately on contact with water,' says co-author James Gardner, a researcher at KTH. 'We have proven that our alloyed perovskite can survive for several minutes completely immersed in water, which is over a 100 times more stable than the perovskite alone. What's more, the solar cells that we have built from the material retain their efficiency for more than 100 days after they are manufactured.'
The researchers report that the cells' power conversion efficiency dropped by 20 percent after six months at a relative humidity of 25 to 80 percent; and they could be completely immersed in water for a few minutes before degradation started.
Gardner says that the 2D perovskite coating also mitigates energy losses in the light-absorbing 3D perovskite, which leads to an enhancement in the photovoltage. The findings indicate that long-chain alkylammonium cation-based 2D perovskites can improve the environmental stability of 3D-based perovskites, without significant loss of performance and may lead to commercially successful perovskite solar cells.
