Study of a Lead-Free Perovskite Solar Cell Using CZTS as HTL to Achieve a 20% PCE by SCAPS-1D Simulation

Area of Science:

• Materials Science
• Renewable Energy
• Semiconductor Physics

Background:

• Perovskite solar cells (PSCs) offer promising photovoltaic potential.
• Developing lead-free alternatives is crucial for environmental safety and sustainability.
• Tin-based perovskites present a viable lead-free option with tunable properties.

Purpose of the Study:

• To simulate and optimize a novel n-i-p planar heterojunction perovskite solar cell (PSC) utilizing tin-based materials.
• To investigate the performance of a lead-free PSC architecture for efficient solar energy conversion.
• To identify optimal device parameters for maximizing the power conversion efficiency (PCE) of the proposed solar cell.

Main Methods:

• Device simulation using Solar Cell Capacitance Simulator (SCAPS-1D) under standard AM 1.5G illumination.
• Optimization of key parameters including absorber layer thickness (MASnI3 and CZTS), CZTS band gap, operating temperature, acceptor concentration, and defect density.
• Fabrication of a n-i-p planar heterojunction structure with Fluorine-doped tin oxide (FTO), TiO2 ETL, MASnI3 absorber, CZTS HTL, and Gold back contact.

Main Results:

• Optimized absorber thicknesses of 500 nm for MASnI3 and 300 nm for CZTS were determined.
• Optimal acceptor density (N) of 10^16 cm^-3 and defect density (N) of 10^14 cm^-3 for the absorber layer yielded the best performance.
• Achieved simulation results include a short-circuit current density (Jsc) of 31.66 mA/cm², an open-circuit voltage (Voc) of 0.96 V, a fill factor (FF) of 67%, and a power conversion efficiency (PCE) of 20.28%.

Conclusions:

• The simulated lead-free tin-based perovskite solar cell demonstrates significant potential for efficient solar energy harvesting.
• The optimized device architecture and parameters provide a strong foundation for future development of sustainable PSCs.
• The proposed structure is suitable for integration into solar energy harvesting systems, contributing to renewable energy solutions.