New synergistic doping strategy could enable more efficient and stable perovskite solar cells
Researchers from China's Westlake University, Fudan University and Zhejiang University have explained that while record power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) are usually achieved using organic spiro-OMeTAD, conventional doping with hygroscopic dopants (LiTFSI and tBP) leads to compromised device stability.
Image of spiro-OMeTAD solutions with various dopants alongside filtered 5D spiro-OMeTAD solutions. Image from: Nature Communications
In their recent work, the team introduced a synergistic mixed doping strategy that utilizes a combination of metal-TFSI dopants—LiTFSI, KTFSI, NaTFSI, Ca(TFSI)2, and Mg(TFSI)2—to enhance doping efficiency while effectively removing hygroscopic contaminants from the Spiro-OMeTAD solution. This approach enables PCEs exceeding 25% and significantly improved stability under harsh environmental conditions.