A research team from Swansea University’s SPECIFIC Innovation and Knowledge Centre has created a printable perovskite solar module the size of an A4 sheet of paper, almost six times larger than previous models.

Perovskite has gained increasing attention in the solar industry due to its low manufacturing costs, being cheaper and easier to produce than silicon, the most commonly used material in solar cells.

Perovskite solar cells also have high efficacy rates, scoring power conversion efficiency (PCE) rates of up to 22%, only slightly less than the 26% reported from silicon solar cells.

The team used an existing type of printable cell, a carbon perovskite solar cell (C-PSC), which contains layers of titania, zirconia and carbon. Though less efficient than other types of perovskite cell types, C-PSCs have a longer life-span.

The C-PSC was printed onto glass substrates in a variety of sizes, up to the scale of an A4 sheet, with the team using a method called registration to align the layers of different materials.

The manufacturing process was carried out in ambient conditions as, unlike silicon fabrication, perovskite does not require an expensive high-vacuum environment.

Further testing showed the team’s module had a PCE of up to 6.3% when examined against the ‘one sun standard’, or full simulated sunlight. Such results are record-breaking for a module of this scale.

In light levels of 200 lux, the module had an 11% PCE, and an 18% PCE at 1,000 lux. This demonstrates the module’s efficacy in indoor lighting, and implies the technology can be used to power electronic devices both inside and out.

Study co-author Dr Francesca De Rossi said: “Our work shows that perovskite solar cells can deliver good performance even when produced on a larger scale than reported so far within the scientific community. This is vital in making it economical and appealing for industry to manufacture them.

“The key to our success was the screen printing process. We optimised this to avoid defects caused by printing such large areas. Accurate registration of layers and patterning the blocking layer helped improve connections between cells, boosting overall performance.”

According to De Rossi, the team is now looking to increase the ‘active area’ of the module, boosting the surface area capable of generating power.