Photovoltaic ink could lead to easy solar panel production

IN solar panels, silicon material has an unassailable lead. The reason for the lack of an alternative material has been the low traction of thin-film technologies as raw materials were costly and inefficient.

As an alternative to silicon, research has been expanding on perovskite solar cells considering its abundance and potential for higher efficiencies. This is despite its limitations to suit the conditions of mass manufacturing and the problem of material decay. In mitigating the decay problem, scientists at the National Renewable Energy Lab (NREL) had been conducting research.

The starting point of the photovoltaic ink was the formation of a simple perovskite from a mixture of iodine, lead and methylammonium.

Though the material could form photovoltaic crystals easily the problem of slow drying at higher temperatures was a drag as it would make manufacturing slow and will also add cost up costs. To address the problem, the team deployed a “negative solvent” by substituting chlorine for the iodine. The experiment was aimed at hastening crystal formation and faster settling. It worked and the perovskite ink dried up in a minute even at 100 degrees Celsius onto a surface.

Drying at such high speeds is a boon in roll-to-roll manufacturing in which spun off sheets are added and rolled back frequently.

The ink also gave positive results in blade coating where more ink is applied with the unused part chipped out while running the coated surface beneath a blade.

In terms of efficiency, ink coated individual cells showed good efficiencies at 17 per cent and beyond. Fullerenes coating escalates the efficiency further taking it to 19 per cent and above. However, silicon does not offer such a flexibility though it is easier to produce.