The researchers of EPFL are expanding the dimensions of perovskite solar cell performance by discovering the finest method to grow these crystals.
Michael Graetzel and his team’s members discovered that by slightly diminishing the pressure while engineering perovskite crystals, they were able to secure the best performance ever calculated for bigger-size perovskite solar cells, reaching to over 20% efficiency and reaching the performance of traditional thin-film solar cells of equivalent sizes.
It is lucrative news for the perovskite technology that will help it to reduce the cost and boost industrial development. But, high performance in perovskites does not essentially represent the doom of silicon-based solar technology. Security issues still require being reported concerning the lead content of current perovskite solar cell prototypes along with defining the stability of actual units.
Placing perovskites above the silicon to create hybrid solar panels may truly augment the silicon solar-cell industry. Efficacy could surpass 30% with the theoretical level being around 44%. The enhanced performance would come from harnessing higher solar energy. The greater the energy light would be captivated by the perovskite top layer, while reducing lesser energy sunlight moving through the perovskite would be engrossed by the silicon layer.
Graetzel is well-known for his translucent dye-sensitized solar cells. It converts out of that the foremost perovskite solar cells were dye-sensitized cells where minor perovskites particles substituted the dye.
The latest perovskite prototype of his lab, which is approximately the size of an SD card, appears like a unit of glass that is darkened on one side by a sleek film of perovskite. The perovskite solar cell is not like the transparent dye-sensitized cells and is opaque.
For making a perovskite solar cell, the researchers must cultivate crystals that have a unique structure, known as ‘perovskite’ named after a Russian mineralogist Lev Perovski, who founded it. The researchers initially melt a mixture of compounds in a liquid to craft some ink. They then laid the ink on a unique type of glass that holds the proficiency to generate electricity. The ink dries in some time and leaves behind a sleek layer that crystallizes on the top layer of the glass when the mild amount of heat is applied. Eventually, it resulted in a thin layer of perovskite crystals.
The complicated part is cultivating a sleek film of perovskite crystals so that the ultimate solar cell absorbs a higher amount of light. Researchers are regularly searching for regular and smooth layers of perovskite with big crystals grain size to enhance photovoltaic yields.
There can be similar instances, like spinning the cell when the ink has partially dried, and an excess amount of liquid is wicked off, resulting in more typical films. A novel vacuum flash method utilized by Graetzel and his panel also selectively eradicates the volatile component of this surplus liquid. At the same instance, the burst of vacuum flash generates seeds for the formation of crystals, resulting in regular and glittery perovskite crystals of greater electronic quality.