Perovskite Solar Cell Remains Stable For Over A Year

EPFL scientists’ 2D/3D hybrid cell delivers 11.2 percent efficiency without performance loss

EPFL scientists have built a low-cost and ultra-stable perovskite solar cell that has been running at 11.2 percent efficiency for over a year, without loss in performance. Their work is published in Nature Communications.

Perovskite solar cells promise cheaper and efficient solar energy, with enormous potential for commercialization. But even though they have been shown to achieve over 22 percent power-conversion efficiency, their operational stability still fails market requirements.

Despite a number of proposed solutions in fabrication technology, this issue has continued to undercut whatever incremental increases in efficiency have been achieved.

The lab of Mohammad Khaja Nazeeruddin at EPFL, in collaboration with Michael Grätzel and Solaronix, has engineered what is known as a 2D/3D hybrid perovskite solar cell. This combines the enhanced stability of 2D perovskites with 3D forms, which efficiently absorb light across the entire visible spectrum and transport electrical charges.

In this way, the scientists were able to fabricate of efficient and ultra-stable solar cells, which is a crucial step for upscaling to a commercial level. The 2D/3D perovskite yields efficiencies of 12.9 percent (carbon-based architecture), and 14.6 percent (standard mesoporous solar cells).

The scientists built 10×10 cm² solar panels using a fully printable industrial-scale process. The resulting solar cells have now delivered a constant 11.2 percent efficiency for more than 10,000 hours, while showing zero loss in performance as measured under standard conditions.

The breakthrough resolves the problem of perovskite solar-cell stability, and can viably move the technology into the commercial sphere.

This work was funded by the Marie Curie Institute, the Horizon 2020 program, the European Union Seventh Framework Programme (FP7/2007-2013) and Solaronix.

‘One-Year stable perovskite solar cells by 2D/3D interface engineering’ by G. Grancini et al; Nature Communications 01 June 2017. DOI: 10.1038/ncomms15684