Multi-Functional Interface Engineering for Monolithic Perovskite/Perovskite/Crystalline Silicon Triple-Junction...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite/perovskite/silicon triple-junction tandem solar cells (TSCs) offer high efficiency potential.
• Wide-bandgap (WBG) perovskite top subcells are key for TSC efficiency.
• Defects and poor energy alignment in WBG perovskite films cause significant energy loss.

Purpose of the Study:

• To enhance WBG perovskite films using multifunctional interface engineering.
• To improve the properties of 2.03 eV perovskite films for solar cell applications.
• To advance the efficiency of single-junction perovskite solar cells (PSCs) and triple-junction TSCs.

Main Methods:

• Interface engineering of 2.03 eV perovskite films using piperazinium bromide (PZBr).
• Utilizing PZBr's molecular structure to passivate defects and suppress phase segregation.
• Improving energy band alignment and facilitating crystal ripening in perovskite films.

Main Results:

• PZBr modification suppressed non-radiative recombination and accelerated carrier extraction.
• Single-junction 2.03 eV PSCs achieved a 13.82% efficiency.
• Monolithic triple-junction TSC reached a 20.05% champion efficiency with a 2.96 V photovoltage.

Conclusions:

• PZBr-based interface engineering is critical for advancing WBG PSCs.
• This approach significantly improves the performance of triple-junction TSCs.
• The study highlights the potential of PZBr for high-efficiency perovskite solar technologies.