New perovskite-silicon solar cell pushes the limits of efficiency

Commercial silicon-based solar cells have made significant improvements in efficiency over the past decade, increasing from around 15% efficiency in 2015 to just shy of 25% in 2025.

In the quest to surpass previous efficiency limits, researchers are moving on from purely silicon-based designs and are exploring the potential of adding a self-assembling monolayer of perovskite on top of a traditional silicon solar cell. This tandem design has already shown great promise, but researchers have struggled to precisely control the thickness and orientation of self-assembled monolayer (SAM) materials.

In a new paper published in the journal Nature, a team of Chinese researchers describe their innovative approach to controlling the properties of self-assembled monolayer (SAM) materials, enabling them to achieve 34.58% power conversion efficiency in a silicon-perovskite tandem solar cell design.

The innovation is based on researchers developing a technique to have perovskite molecules self-assemble on top of a transparent oxide layer. This SAM design, called HTL201, has a number of favorable qualities, including low parasitic absorption (meaning more of the photons are available for energy production) and rapid extraction capabilities.

This process forms a denser, more uniform monolayer on the transparent conductive oxide layer, which allows for stronger interaction between HTL201 and the perovskite film.

In tests of a one-centimeter square sample under standard illumination conditions, the new solar-cell design achieved power conversion efficiency of 34.58%.

Perovskite-based materials, like the one developed by this team, are very good at absorbing sunlight and even outperform silicon at blue and green wavelengths. They are also relatively inexpensive to produce.

Though the new design was able to achieve remarkable efficiency, the researchers did not explore methods to scale up their process. The tests were also conducted under laboratory conditions, which did not account for the impacts of humidity and temperature. Heat is well known to significantly limit the efficiency of silicon-based solar cells.

With the development of more efficient and stable perovskite/silicon TSCs, this approach has the potential to lower the cost of solar power and accelerate the adoption of renewable energy alternatives.

The researchers write in their paper, “Our research provides critical technical solutions for developing novel SAM materials and further advancing silicon-perovskite tandem efficiency.”

© 2025 Science X Network