Optimizing Charge Transport Layers to Enhance the Performance of Lead-Free RbGeI₃ Perovskite Solar Cells: A...

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Physics

Background:

• Hybrid perovskite solar cells are a promising renewable energy technology.
• Rubidium-germanium-iodide (RbGeI₃) presents a novel substrate for perovskite solar cells.
• Optimization of hole and electron transport layers is crucial for device efficiency.

Purpose of the Study:

• To investigate innovative hybrid perovskite solar cells utilizing RbGeI₃ as the substrate.
• To explore the impact of various hole transport layers (Cu₂O, CuO, SnSe) and electron transport layers (ETLs).
• To optimize device configuration and parameters for maximum power conversion efficiency.

Main Methods:

• Fabrication and simulation (SCAPS-1D) of three hybrid perovskite solar cell configurations.
• Selection and optimization of Indium Gallium Zinc Oxide (IGZO) as the optimal ETL.
• Detailed analysis of doping concentration, layer thickness, defect density, temperature, and interface defects.

Main Results:

• Device I (Al/FTO/IGZO/RbGeI₃/Cu₂O/Ni) achieved a power conversion efficiency (PCE) of 33.84%, a fill factor of 86.78%, an open-circuit voltage (V_OC) of 1.13 V, and a short-circuit current density (J_SC) of 34.54 mA/cm².
• Devices II and III exhibited PCEs of 25.91% and 25.21%, respectively.
• Comprehensive analysis of resistances, generation-recombination rates, carrier dynamics, and quantum efficiency.

Conclusions:

• RbGeI₃-based hybrid perovskite solar cells demonstrate significant potential for high-efficiency photovoltaic applications.
• Device I sets a new benchmark for RbGeI₃ solar cells, highlighting the effectiveness of the Cu₂O HTL and IGZO ETL.
• Further research into interface engineering and defect mitigation can lead to even higher performance.