High-Efficient Cs₂AgBiBr₆ Perovskite Solar Cells with Rare-Earth-Doped Absorber and Front Contact: A Numerical...

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Physics

Background:

• Perovskite solar cells (PSCs) offer high efficiency but often rely on hole transport layers (HTLs) that can degrade device stability.
• Developing HTL-free PSCs is crucial for improving long-term performance and simplifying fabrication.
• Cs₂AgBiBr₆ is a promising material for stable, lead-free PSCs.

Purpose of the Study:

• To propose and theoretically investigate a novel, simplified HTL-free PSC structure.
• To enhance the stability and efficiency of Cs₂AgBiBr₆-based PSCs through praseodymium (Pr³⁺) doping.
• To optimize device parameters using simulation for maximum performance.

Main Methods:

• Fabrication of a simplified HTL-free PSC structure using Pr³⁺-doped Cs₂AgBiBr₆.
• Device performance simulation using Solar Capacitance Simulation Software (SCAPS-1D) version 3.3.10.
• Systematic analysis of device parameters including absorber thickness, defect density, ETL properties, and back-contact work function.

Main Results:

• The Pr³⁺-doped PSC with Tb-FTO front contact achieved a simulated PCE of 7.91%.
• Optimization of device parameters led to a predicted PCE of 19.93% (V_oc = 0.85 V, J_sc = 27.73 mA/cm², FF = 84.51%).
• Further optimization with a higher metal work function (Se, 5.9 eV) predicted a PCE of ~27.65% (V_oc = 1.20 V, J_sc = 27.78 mA/cm², FF = ~82.69%).

Conclusions:

• The proposed HTL-free PSC structure demonstrates significant potential for high efficiency and improved environmental stability.
• Pr³⁺ doping and optimized device parameters are key to achieving high performance in Cs₂AgBiBr₆ PSCs.
• The theoretical findings provide a strong foundation for future experimental validation and development of stable, efficient HTL-free PSCs.