Fluoride boosts water-processed perovskite solar cells

A research team at Queensland University of Technology (QUT) has developed an eco-friendly method to fabricate perovskite solar cells (PSC) by incorporating a fluoride additive into a water-based solution.

Large-scale commercialisation of PSCs has been limited by environmental and health risks linked to the use of toxic organic solvents in the fabrication process. Water-based processing provides a greener alternative, but the end product has a lower device performance.

The QUT research team’s new approach eliminates the use of these toxic solvents, while also achieving power conversion efficiencies above 18%.

In the study, QUT researchers introduced lead(II) fluoride (PbF₂) into the water-based precursor solution to regulate crystal growth dynamics and improve film quality. The fluoride additive accelerated the formation of the photoactive phase and promoted the crystallisation orientation, both critical for efficient solar energy conversion. Additionally, the high electronegativity of fluoride ions helped passivate surface defects on perovskite grains, reducing energy losses and enhancing charge transport.

“With the PbF₂ additive, we achieved a power conversion efficiency of 18.1%, compared to 16.3% in the control device,” said Dr Minh Tam Hoang, postdoctoral researcher at QUT and author of the study. “Even more exciting is the improved operational and environmental stability, which brings us closer to scalable, green manufacturing of PSCs.”

This research provides an effective strategy to produce stable, high-efficiency PSCs using water solvent — making the technology more viable for commercial production and reducing environmental impacts. It also highlights the growing importance of fluoride-based additives in green chemistry and sustainable energy technologies.

The study was recently published in the online edition of Materials Futures, a journal in materials science and clean energy research.

Image caption: Fluoride additive enhances performance of perovskite solar cells using water-based fabrication. Image credit: Minh Tam Hoang and Hongxia Wang from Queensland University of Technology.