Simultaneous Li-Doping and Formation of SnO₂-Based Composites with TiO₂: Applications for Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Tin oxide (SnO2) is crucial for electron transport layers (ETLs) in perovskite solar cells (PSCs) due to its high electron mobility.
• Current ETLs require optimization for enhanced electron extraction and transport in PSCs.

Purpose of the Study:

• To develop a novel heat treatment process for SnO2-based ETLs using Li/TTIP precursors.
• To investigate the impact of heat treatment on nanoparticle sintering and Li-doping concentration.
• To explore the formation of Li-doped SnO2/TiO2 solid solutions for improved photovoltaic performance.

Main Methods:

• Fabrication of double-layer films comprising SnO2 nanoparticles and an Li/TTIP precursor.
• Varied heat treatment conditions to optimize nanoparticle interconnection and Li-doping.
• Characterization using X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM).

Main Results:

• Successful formation of an Li-doped SnO2/TiO2 solid solution via heat treatment.
• Observed sintering of SnO2 nanoparticles, enhancing interconnection.
• The Li-doped ETL exhibited a narrower bandgap (3.45 eV) compared to pure SnO2.

Conclusions:

• The developed heat treatment process offers a new approach for creating advanced ETLs in PSCs.
• Li-doped SnO2/TiO2 solid solutions show promise for optimizing perovskite solar cell performance.
• This method provides an alternative to conventional SnO2 ETLs for enhanced device efficiency.