Theoretical investigation of FAPbSnGeX₃ efficiency

Area of Science:

• Materials Science
• Solid State Physics
• Renewable Energy

Background:

• Hybrid lead halide perovskites are promising for photovoltaics due to excellent optoelectronic properties.
• The presence of toxic lead in these materials poses environmental concerns.
• Developing lead-reduced alternatives is crucial for sustainable solar energy.

Purpose of the Study:

• To investigate the structural, electronic, and optical properties of novel lower-lead perovskites (FAPb0.5Sn0.25Ge0.25X3).
• To evaluate their photovoltaic performance, including open-circuit voltage, short-circuit current density, and power conversion efficiency.
• To compare these properties against traditional lead-based perovskite structures (FAPbX3).

Main Methods:

• Utilized density functional theory (DFT) for systematic property analysis.
• Calculated electronic band gaps, adsorption coefficients, and stability metrics.
• Modeled photovoltaic parameters such as open circuit voltage (Voc), short circuit current density (Jsc), and power conversion efficiency (η).

Main Results:

• The novel perovskites (FAPb0.5Sn0.25Ge0.25X3) exhibit suitable band gaps for solar cell applications, with iodine compounds showing lower gaps than chlorine.
• Germanium and tin doping significantly enhance adsorption coefficients and material stability compared to lead-only counterparts.
• FAPb0.5Sn0.25Ge0.25Cl3 demonstrated the highest calculated photovoltaic efficiency, despite a decrease in Jsc from iodide to chloride variants.

Conclusions:

• The studied lower-lead perovskites show potential for environmentally friendly and efficient photovoltaic devices.
• FAPb0.5Sn0.25Ge0.25Cl3 emerges as a promising candidate for high-efficiency solar cells.
• This research contributes to reducing the environmental impact of perovskite solar cells while improving their experimental power conversion efficiency.