A recent study involving with UNIST has presented highly stable perovskite solar cells (PSCs) using edged-selectively fluorine (F) functionalized graphene nanoplatelets (EFGnPs). This has gotten a lot of attention because it is made out of fluorine, a low-cost alternative to gold.
The study was jointly led by Professor Jin Young Kim from the School of Energy and Chemical Engineering at UNIST in collaboration with Dong Suk Kim from the Korea Institute of Energy Research (KIER). Assistant Professor Gi-Hwan Kim from the School of Energy and Chemical Engineering at UNIST was the lead author of this study.
Perovskite solar cells (PSCs) have attracted more attention in the past few years as the next generation solar cells that have the potential to surpass silicon cells’ efficiently. The stability and cost issues in PSCs seem to block further advancements towards commercialization.
The perovskite materials are easily decomposed in moisture conditions. They can’t survive even for one day without the proper encapsulation which results in low stability. In order to solve these issues and make progress toward the commercialization of PSCs, Professor Kim and his team introduced a highly stable p-i-n structure for PSCs using fluorine functionalized EFGnPs to fully cover the perovskite active layer and protect against the ingress of water for high-stability PSCs.
"Fluorocarbons, such as polytetrafluoroethylene (Teflon) are well-known for their superhydrophobic properties and comprise carbon-fluorine (C-F) bonding," said Professor Gwi-Hwan Kim at UNIST. "By substituting carbon for fluorine, we have created a two-dimensional material with high hydrophobicity, like Teflon, then, applied it to PSCs."
"This study overcame the weakness of perovskite solar cells that have high efficiencies but low stability," said Professor Jin Young Kim. "This breakthrough holds substantial promise as the base technology for the application of the next-generation solar cells, as well as various IoT devices and displays."
The newly-developed perovskite solar cell device was fabricated using solution processes, a process that involves the coating perovskite materials on a flexible film. Using this process allows the future application of solar cells to wearable devices. The next-generation of solar cells is beneficial because they have a simple manufacturing process and a low manufacturing cost when compared the existing silicon-based inorganic electronic devices.
The paper on this research was published in Nano Letters.