Yttrium oxide engineered substrate enables improved durability for perovskite solar cells.

Area of Science:

• Materials Science
• Renewable Energy
• Semiconductor Physics

Background:

• Transparent conductive oxides (TCOs) are essential for perovskite solar cells (PSCs).
• The stability of fluorine doped tin oxide (FTO), a common TCO, under operational stress is often overlooked.
• FTO instability can exacerbate the overall stability issues in PSCs.

Purpose of the Study:

• To investigate the instability of FTO under operational stress in PSCs.
• To develop a universal interface engineering strategy to enhance the structural stability of FTO.
• To improve the operational stability and performance of PSCs.

Main Methods:

• Interface engineering of FTO using scalable thermal evaporation of yttrium followed by natural oxidation.
• Formation of an atomically bonded yttrium oxide (Y2O3) layer on FTO.
• Characterization of the structural integrity, interfacial adhesion, and barrier properties of the Y2O3/FTO interface.

Main Results:

• Yttrium evaporation and subsequent oxidation form a stable Y2O3 layer on FTO, preventing elemental dissociation.
• The Y2O3 layer enhances interfacial adhesion and acts as a robust barrier against ion diffusion and recombination.
• Unencapsulated PSCs with the engineered interface showed negligible performance loss after 1,200 hours of continuous illumination.
• High power conversion efficiencies achieved: 26.48% (regular), 26.34% (inverted), and 28.47% (tandem).

Conclusions:

• The proposed interface engineering strategy effectively addresses FTO instability in PSCs.
• The Y2O3 interlayer significantly improves the structural integrity and operational stability of PSCs.
• This approach demonstrates strong generality and commercialization potential for high-performance and stable PSCs.