Researchers from The University of Manchester have reported a new method that makes use of polystyrene particles (rather than expensive polymers) to reduce the costs and improve the stability of next-gen perovskite-based solar cells.

U of Manchester team uses polystyrene to improve perovskite PVs image

PSCs that use organometallic halide perovskite (OHP) as a light absorber face a known challenge of material degradation when exposed to water. This makes practical use quite limited. The cells also rely on a hole-transportation layer, which promotes the efficient movement of electrical current after exposure to sunlight. But manufacturing the hole-transportation organic materials is very costly and these lack long-term stability. This is where the use of insulating polystyrene microgel particles comes in.

The team from the School of Materials at The University of Manchester, says: "More research is required to enable the full potential of the exciting PSC technology to be realized. Improving PSC stability and reducing expensive hole-transport material (HTM) use are two aspects that are gaining increased attention. That is why we're looking at how best to produce PSCs, keep them dry and make them even more commercially viable in the future."

The researchers explain: "The perovskite layer in solar cells is not inherently unstable, but the required HTM layer is. HTM layers made of congregated polymers are thin but they are also relatively expensive and contribute a significant portion of the total cost of the solar cell. In this study we used polystyrene, which is 1 ten thousandth of the cost of polymers to produce, and is also hydrophobic which helps improve the stability of PSCs. Overall the enhanced stability and lower costs of production hugely outweigh any of the decreased efficiency."

Going forward the team plans to further refine the microgel approach to minimize the impact on efficiency and work on reducing toxic lead content in PSCs.