Copper (II) Chloride Mediated Interfacial Permeation for High-Efficient and Stable Wide-Bandgap Perovskite Solar...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Wide-bandgap perovskite solar cells (WBG PSCs) are key for high-efficiency tandem applications.
• Interfacial lattice disorder in WBG PSCs causes defects, hindering performance.
• Non-radiative recombination and halide segregation are major challenges.

Purpose of the Study:

• To develop a strategy for stabilizing the buried interface in WBG PSCs.
• To suppress deep-level defects and improve interfacial morphology.
• To enhance the phase stability and charge-transport properties of WBG PSCs.

Main Methods:

• Utilized a copper (II) chloride (CuCl2) mediated interfacial permeation strategy.
• Implemented redox mediation and halide coordination to stabilize the interface.
• Constructed an efficient hole-transfer structure at the buried interface.

Main Results:

• Minimized lattice disorder and deep-level defects at the buried interface.
• Achieved superior charge-transport properties and enhanced interfacial phase stability.
• Modified 1.79 eV WBG PSCs reached a V_OC of 1.35 V, FF of 84.29%, and PCE of 21.24%.

Conclusions:

• The CuCl2 strategy effectively stabilizes WBG PSC interfaces.
• The approach significantly reduces non-radiative recombination losses.
• The developed WBG PSCs demonstrate state-of-the-art performance and long-term stability (91% after 1400h).