Stable perovskite solar cells with efficiency exceeding 24.8% and 0.3-V voltage loss

Operating in wet conditions The high efficiency of the complex organic molecule Spiro-OMeTAD as a hole-transporting material for perovskite solar cells requires the use of hygroscopic dopants that decrease stability. Jeong et al. synthesized hydrophobic fluorinated analogs of Spiro-OMeTAD as hole-transporting materials that have favorable shifting of the electronic state for hole extraction and used them to fabricate perovskite solar cells. A champion device had a certified power conversion efficiency of 24.8% and an open-circuit voltage near the Shockley-Queisser limit. These devices could maintain more than 87% of the original power conversion efficiency under 50% relative humidity for more than 500 hours. Science , this issue p. 1615