Work that shows that perovskite solar cells can perform well even when produced on a large scale. They get new efficiency record for a printed perovskite photovoltaic module.

About the size of an A4 sheet of paper, you only need a printer to produce it, with methods common in the printing industry which are also simple and inexpensive. We are talking about the innovative perovskite photovoltaic module developed by researchers at the University of Swansea, UK.

What is so special? A perovskite solar module with a surface almost six times greater than that of panels manufactured so far with this technology (10 cm2), a necessary step to be able to market it and be able to compete with the current ones.

Perovskite is probably one of the materials in which more research is currently being done to increase the efficiency and reduce the costs of solar energy. It is cheaper than silicon, the material with which the vast majority of solar panels are made, and its potential efficiency is greater. Scientists are researching to increase their power generation capacity, setting new efficiency records almost every month, although silicon has yet to be beaten. But it seems it’s only a matter of time.

Its creators published an article in Advanced materials technologies where they explain the progress made, explaining that the whole manufacturing process is simple and inexpensive.

The secret to the success of the Swansea researchers has been the process of printing the modules. To avoid the defects associated with prints of this size, which could decrease their efficiency due to possible connection problems between cells, they used a technique well known in the printing industry: registration, which guarantees that the patterns and the layers that make up the module are perfectly aligned and, therefore, the connection between the different cells is perfect. This is why they managed to make the modules so big without losing their efficiency due to small printing defects.

The new perovskite photovoltaic module is made up of C-PSC (Carbon-Pervoskite based Solar Cells) units: these cells are formed by serigraphs that print three mesoporous layers of titanium, zirconia and carbon arranged one on top of the other, and the ‘subsequent infiltration of a liquid perovskite precursor through them.

Unlike their “sisters”, the C-PSC have significantly lower yields: if the “classic” perovskite photovoltaic technology has already exceeded 23%, for these units equipped with carbon the value, in the best case, is of the order of 10%. However, they do not degrade as quickly and have already proven that they can maintain their performance under continuous lighting after more than a year of operation.

The innovation of the Swansea team is linked to the optimization of the printing process on glass substrates the size of an A4 sheet of paper.

The entire process was carried out under normal environmental conditions, without the need for expensive vacuum systems necessary for the production of silicon solar cells.

The Swansea team achieved good results for their modules: “The results speak for themselves: the module exhibits an energy conversion efficiency of up to 6.3% when evaluated in fully simulated sunlight. This value is the highest value ever for a C-PSC device of this size. It also shows 11% efficiency at 200 lux, which is about the same as light levels in a normal living room.. “

Our work shows that perovskite solar cells can perform well even if produced on a larger scale than has been done so far in the scientific community.», Explains Dr Francesca De Rossi, project manager. “This is essential to make it economical and attractive for industrial production. […] There is still a lot of work to be done, like increasing the active surface, but we are already working on it. “