Guanidinium stabilizes perovskite solar cells at 19% efficiency

Typography

With the power-conversion efficiency of silicon solar cells plateauing around 25%, perovskites are now ideally placed to become the market’s next generation of photovoltaics. In particular, organic-inorganic lead halide perovskites offer manufacturing versatility that can potentially translate into much higher efficiency: studies have already shown photovoltaic performances above 20% across different solar cell architectures built with simple and low-cost processes.

With the power-conversion efficiency of silicon solar cells plateauing around 25%, perovskites are now ideally placed to become the market’s next generation of photovoltaics. In particular, organic-inorganic lead halide perovskites offer manufacturing versatility that can potentially translate into much higher efficiency: studies have already shown photovoltaic performances above 20% across different solar cell architectures built with simple and low-cost processes.

The main challenge for the perovskite field is not so much efficiency but stability. Unlike silicon cells, perovskites are soft crystalline materials and prone to problems due to decomposition over time. In a commercial context, this puts perovskites on a higher price tag than conventional silicon cells.

There have therefore been many efforts in synthesizing perovskite materials that can maintain high efficiency over time. This is done by introducing different cations (positively charged ions) into the crystal structure of the perovskite. Although success has been reported by mixing inorganic cations like cesium or rubidium into the perovskite composition, these solutions tend to be difficult and expensive to implement.

Read more at École Polytechnique Fédérale de Lausanne (EPFL)

Image: Perovskite solar cell prototype. Credit: Alain Herzog / EPFL