Chinese scientists have developed a new method that could facilitate the large-scale production of high-efficiency perovskite solar cells. The method employs a multidentate anchoring molecule-assisted co-deposition strategy to improve the fabrication of self-assembled monolayers (SAMs) through blade coating—a technique that applies a thin film to a substrate with a blade and is suitable for large-scale manufacturing.
The study, published in Chem on August 10, was led by researchers from the research group of Prof. PANG Shuping at the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences (CAS), along with the research group of Prof. ZHOU Zhongmin at Qingdao University of Science and Technology.
SAMs have emerged as promising hole-selective interlayers for high-efficiency inverted perovskite photovoltaics because of their efficient charge extraction and minimal material consumption.
However, commonly used phosphonic acid-based SAM molecules tend to aggregate in solution. During blade coating, such aggregation can lead to incomplete surface coverage, poor wettability, and spatially nonuniform interfaces, thereby limiting device reproducibility and large-area manufacturing.
To address this challenge, the researchers incorporated pentaerythritol tetra(3-mercaptopropionate) (PMP), a dendritic tetradentate thiol-anchoring molecule, into a Me-4P SAM matrix.
They found that PMP interacts strongly with Me-4P through intermolecular hydrogen bonding. These interactions suppress Me-4P self-aggregation and improve its dispersion during solution processing, enabling blade coating to produce a more continuous and uniform SAM layer.
Following film deposition, some of the uncoordinated terminal thiol (-SH) groups remain exposed on the film surface. These hydrophilic groups allow the perovskite precursor to wet the SAM interface more effectively, resulting in more uniform deposition and improved crystallization.
The co-deposition strategy also reduced residual interfacial stress, strengthened adhesion at the buried interface, and passivated defect states, thereby improving the structural and electronic quality of the perovskite films.
With improved anchoring and interfacial contact, small-area devices achieved a champion power conversion efficiency of 26.60%, with a certified efficiency of 26.23%. A 20.9 cm 2 mini-module reached an efficiency of 23.31%, demonstrating the scalability of the approach. It was also compatible with several commonly used SAM systems.
The researchers noted that the devices also exhibited strong long-term stability. They retained 96% of their initial efficiency after 1000 hours of continuous operation under the ISOS-L-1 protocol and maintained 91% after 1000 hours of thermal aging at 85 °C under the ISOS-D-2 protocol.
According to the researchers, this approach provides a practical pathway for transferring high-performance SAM interfaces from laboratory-scale spin coating to scalable blade coating, bringing SAM-based inverted perovskite photovoltaics closer to large-area manufacturing.
Chem
Experimental study
Not applicable
Multidentate Anchoring Molecule-Assisted Blade-Coated Self-Assembled Monolayer for Scalable and Stable Perovskite Photovoltaics
10-Aug-2026