Thanks to a new coating technique, a team of scientists were able to manufacture 21 cm square perovskite photovoltaic modules with unprecedented conversion efficiency.

Thermal co-evaporation gives perovskite mini solar panels an efficiency of 18.1%.

A team of scientists carried out increase the performance of the next generation of photovoltaic energy through the use of a process used in the manufacture of OLED televisions.

It was developed at Nanyang Technological University (NTU) in Singapore, where researcher Annalisa Bruno and a few colleagues produced mini solar panels with record efficiency.

The material chosen is perovskite, a material which in a very short time has reached silicon standards.

Unlike conventional semiconductor, it has proven to be particularly effective in creating lightweight, flexible and semi-transparent photovoltaic cells.

Perovskite-based devices are rapidly moving towards industrialization, but stability and scalability remain hurdles to overcome before commercialization.

NTU’s research is part of a process that shortens the transition from laboratory to market.

The key point of the work is in the coating technique with which they produced the mini solar modules.

So far, the best performing perovskite solar cells have been made in the lab much smaller than a square centimeter, using a solution-based technique called spin coating. However, when used over a large area, the method results in cells with lower energy conversion efficiencies. This is due to inherent limitations including defects and non-uniformity over large areas, making industrial manufacture difficult.

Annalised Bruno.

Scientists adopted a different industrial coating technique called “thermal coevaporation,” which is now widely used in electronics.

And they found out that they could get 21 square centimeter modules with 18.1% conversion efficiency. These are the highest values ​​recorded in this sector.

Our work demonstrates the compatibility of perovskite technology with industrial processes and its potential for market entry. This is good news for Singapore, which is trying to increase the use of solar energy for its energy needs. Using the same technique, the group manufactured semi-transparent and colored versions of photovoltaic cells and mini perovskite modules, which achieved similar efficiency values.

Annalised Bruno.

Mini solar panels can be used on facades and windows of skyscrapers, which is not possible with current silicon modules because they are opaque and able to block light. It will be possible to incorporate semi-transparent colored solar cells into architectural designs to collect even more solar energy without compromising the aesthetic qualities of your buildings.

Subodh Mhaisalkar, Executive Director of the NTU Energy Research Institute.

The research was published in Joule.

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