Progress in Surface Modification of SnO₂ Electron Transport Layers for Stable Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) show rapid performance gains but face stability challenges hindering commercialization.
• Electron transport layers (ETLs) and their interfaces significantly impact PSC device stability.
• Tin oxide (SnO2) is a common ETL material, but its intrinsic properties can limit PSC operational lifetime.

Purpose of the Study:

• To review the impact of SnO2 ETL modifications on PSC interfacial properties and device stability.
• To categorize strategies for addressing SnO2-related stability issues in PSCs.
• To identify future research directions for enhancing PSC stability via SnO2 ETL engineering.

Main Methods:

• Literature review focusing on SnO2 ETLs in PSCs.
• Analysis of intrinsic SnO2 defects (e.g., defects, surface hydroxyls, morphology) affecting interfaces.
• Categorization of modification approaches: surface morphology control, physicochemical modification, and composite structures.

Main Results:

• Intrinsic SnO2 properties like defects, surface hydroxyls, and nonuniform morphology degrade interfacial quality and PSC stability.
• Surface morphology control, physicochemical modifications, and composite-structure designs are effective strategies to mitigate these issues.
• These modifications improve interfacial contact and charge transport, leading to enhanced device longevity.

Conclusions:

• Addressing SnO2 ETL intrinsic defects and interfacial issues is vital for PSC commercialization.
• Tailoring SnO2 ETLs through surface engineering offers a promising pathway to high-stability PSCs.
• Further research is needed at both material and device levels to fully realize the potential of SnO2 ETLs in stable PSCs.