The first fully solution processable, flexible metal perovskite solar cells have been developed by a team from the College of Engineering based at SPECIFIC Innovation and Knowledge Centre, which is developing a range of functional coatings for building materials: coatings that can be applied to roofs and walls on a large scale, using cost-effective, earth-abundant and safe materials.

Until this breakthrough, the majority of perovskite PV research used flat glass as a base material for the device. This method presents limitations for large-scale continuous manufacturing as it is usually done on a roll-to-roll basis which requiring the material to be flexible. 

Also while there have been advances in the more flexible ‘plastic perovskite’ replacements for glass, the main limitations in their production include: 

• The use of the rare and expensive element, indium which give the plastic an electrically conductive coating.
• The production methods involves vacuum processing which is difficult and costly.

This new development by the research team, which is led by Senior Lecturer Dr Trystan Watson, allows for highly efficient solar cells to be deposited using inexpensive printing techniques onto cheap metal foil without having to use any indium or vacuum processing. They also retain almost all of their original performance when repeatedly bent out of shape.

Lead researcher Joel Troughton said: “This research opens up the possibility of printing photovoltaics directly onto metal building materials in the same way coloured paint is applied in the factory.

“Tata Steel, our SPECIFIC partners, currently produces around 100,000,000m² of metal building cladding per year. If we could print solar cells onto this material, we could put a sizeable dent in the UK and Wales’ carbon footprint, as well as creating jobs in the local economy.”

The paper, 'Highly efficient, flexible, indium-free perovskite solar cells employing metallic substrates', is available in the Royal Society of Chemistry’s Journal of Materials Chemistry A.