At their best, conventional solar cells are one-third efficient, however a newly developed material could change that.
A crystalline structure comprised of both inorganic materials (iodine and lead) and an organic material (methyl-ammonium), could potentially double solar cell efficiency according to a new study in Science.
Deemed a hybrid perovskite, the material would essentially create thinner, more flexible, cheaper, and simple silicon solar cells, says Libai Huang, assistant professor of chemistry at Purdue University.
Just how easy is it to make the new structure?
“My graduate students learn how to make it in a few days,” Huang says.
“The distance hot carriers need to migrate is at least the thickness of a solar cell, or about 200 nanometers, which this new perovskite material can achieve,” Huang adds. “Also these carriers can live for about 100 picoseconds, two orders of magnitude longer than silicon.”
Coauthor Kai Zhu, senior scientist at the National Renewable Energy Laboratory in Golden, Colorado, notes these factors are pivotal when it comes to building a commercial hot-carrier solar cell.
“This study demonstrated that hot carriers in a standard polycrystalline perovskite thin film can travel for a distance that is similar to or longer than the film thickness required to build an efficient perovskite solar cell,” he says. “This indicates that the potential for developing hot carrier perovskite solar cell is good.”
“The next step is to find or develop suitable contact materials or structures with proper energy levels to extract these hot carriers to generate power in the external circuit,” Zhu says. “This may not be easy.”
The material’s future viability will depend on replacing lead in the structure with other, less toxic, metals.