Thiazolidinone-Based Electron-Collecting Monolayers for n-i-p Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Efficient electron-collecting monolayer materials are crucial for cost-effective and high-performance perovskite solar cells (PSCs).
• Current PSCs often utilize a regular (negative-intrinsic-positive, n-i-p) architecture, requiring optimized interfaces for electron extraction.

Purpose of the Study:

• To design and synthesize novel electron-collecting monolayer materials for n-i-p PSCs.
• To investigate the impact of molecular structure, specifically Lowest Unoccupied Molecular Orbital (LUMO) levels and anchoring groups, on material performance.
• To understand the interfacial mechanisms governing electron extraction and PSC efficiency.

Main Methods:

• Synthesis of four thiazolidinone-based monolayer materials with varying LUMO levels (rhodanine/thiazolidinedione) and anchoring groups (phosphonic/carboxylic acid).
• Adsorption of synthesized molecules onto indium tin oxide (ITO) substrates.
• Measurement of ITO work function modification.
• Fabrication and performance testing of perovskite solar cells incorporating the modified ITO electrodes.

Main Results:

• The synthesized monolayer materials effectively lowered the work function of ITO substrates.
• A significant correlation was observed between the work function shift of ITO and the performance of the PSCs.
• The LUMO levels of the monolayer materials themselves showed less correlation with device performance compared to the work function modification.

Conclusions:

• Thiazolidinone-based monolayer materials are effective for modifying ITO work functions in PSCs.
• Work function modification of the transparent electrode is a key factor in enhancing electron extraction and improving PSC performance.
• This approach offers a pathway to develop more efficient and cost-effective perovskite solar cells.