Enhancing Surface Modification and Carrier Extraction in Inverted Perovskite Solar Cells via Self-Assembled...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) show great potential but are limited by defects.
• Inorganic hole-transporting layers (HTLs) like nickel oxide improve PSCs, yet defects persist.
• Self-assembled monolayers (SAMs) are emerging as a strategy to mitigate defects and enhance performance.

Purpose of the Study:

• To engineer a p-i-n perovskite solar cell structure using novel SAM molecules (HC-A1 and HC-A4).
• To investigate the impact of these SAMs on perovskite film morphology, optical properties, and device performance.
• To evaluate the potential of SAMs for defect reduction and efficiency enhancement in PSCs.

Main Methods:

• Fabrication of p-i-n perovskite solar cells incorporating HC-A1 and HC-A4 SAMs as HTLs.
• Characterization of perovskite film morphology, uniformity, and optical properties.
• Measurement of contact angles to assess hydrophilicity and carrier lifetime.
• Performance testing of solar cell devices, including power conversion efficiency and thermal stability.

Main Results:

• HC-A1 and HC-A4 SAMs improved perovskite film grain morphology and uniformity.
• HC-A4 exhibited superior hydrophilic properties (contact angle 50.3°), leading to efficient carrier extraction (117.33 ns carrier lifetime).
• The HC-A4-modified PSC achieved a record 20% power conversion efficiency and maintained stability over 300 hours.

Conclusions:

• Engineered SAMs, particularly HC-A4, effectively reduce defects in perovskite films.
• HC-A4 SAMs significantly enhance perovskite solar cell performance, achieving high efficiency and stability.
• This study highlights SAMs as a promising approach for advancing perovskite solar cell technology.