Polydentate Ligand Reinforced Chelating to Stabilize Buried Interface toward High-Performance Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Interface Engineering

Background:

• The commercialization of perovskite solar cells is hindered by unstable buried interfaces.
• Interfacial defects and stress at the buried interface lead to performance degradation.

Purpose of the Study:

• To develop a strategy for strengthening the buried interface in perovskite solar cells.
• To improve the stability and efficiency of perovskite photovoltaic devices.

Main Methods:

• Utilized a polydentate ligand chelating strategy with bis(2,2,2-trifluoroethyl) (methoxycarbonylmethyl)phosphonate (BTP).
• BTP was employed to passivate defects on SnO2 and perovskite surfaces, mitigate stress, and reduce interfacial energy barriers.

Main Results:

• BTP modification reduced nonradiative recombination and improved interfacial contact.
• Achieved a power conversion efficiency (PCE) of 24.63% for BTP-modified devices fabricated in air.
• Unencapsulated devices retained 98.6% and 84.2% of initial PCE after 3000h ambient aging and 1728h thermal stress, respectively.

Conclusions:

• The BTP-based multidentate ligand strategy effectively enhances buried interface stability in perovskite solar cells.
• This approach offers a viable route for commercializing stable and efficient perovskite photovoltaic technology.