• DOI:10.1038/s41586-021-03964-8
• Corpus ID: 239052065

Perovskite solar cells with atomically coherent interlayers on SnO2 electrodes.

@article{Min2021PerovskiteSC,
  title={Perovskite solar cells with atomically coherent interlayers on SnO2 electrodes.},
  author={Hanul Min and Do Yoon Lee and Junu Kim and Gwisu Kim and Kyoung Su Lee and Jongbeom Kim and Min Jae Paik and Young Ki Kim and Kwang S. Kim and Min Gyu Kim and Tae Joo Shin and Sang Il Seok},
  journal={Nature},
  year={2021},
  volume={598 7881},
  pages={
          444-450
        }
}

• Hanul Min, Do Yoon Lee, +9 authors Sang Il Seok
• Published 1 October 2021
• Materials Science
• Nature

In perovskite solar cells, the interfaces between the perovskite and charge-transporting layers contain high concentrations of defects (about 100 times that within the perovskite layer), specifically, deep-level defects, which substantially reduce the power conversion efficiency of the devices1-3. Recent efforts to reduce these interfacial defects have focused mainly on surface passivation4-6. However, passivating the perovskite surface that interfaces with the electron-transporting layer is difficult, because the surface-treatment agents on the electron-transporting layer may dissolve while coating the perovskite thin film. Alternatively, interfacial defects may not be a concern if a coherent interface could be formed between the electron-transporting and perovskite layers. Here we report the formation of an interlayer between a SnO2 electron-transporting layer and a halide perovskite light-absorbing layer, achieved by coupling Cl-bonded SnO2 with a Cl-containing perovskite precursor. This interlayer has atomically coherent features, which enhance charge extraction and transport from the perovskite layer, and fewer interfacial defects. The existence of such a coherent interlayer allowed us to fabricate perovskite solar cells with a power conversion efficiency of 25.8 per cent (certified 25.5 per cent)under standard illumination. Furthermore, unencapsulated devices maintained about 90 per cent of their initial efficiency even after continuous light exposure for 500 hours. Our findings provide guidelines for designing defect-minimizing interfaces between metal halide perovskites and electron-transporting layers.