Multiphysics Insights Into Carrier‐Ion Interactions and Electrochemical Reactions in Perovskite/Silicon Tandem Solar Cells

Why It Matters

Understanding carrier‑ion‑electrochemical interactions is essential to design stable, high‑efficiency tandem modules for commercial solar markets.

Key Takeaways

• Ionic reactions reshape carrier distribution, lowering efficiency
• Cations react with electrons under reverse bias, causing losses
• Anions react with holes under forward bias, affecting stability
• Simulations guide optimization of tandem architecture and interfaces
• Multi-physics model links ion migration to electrochemical degradation

Pulse Analysis

The rapid rise of perovskite/silicon tandem solar cells (TSCs) stems from their potential to surpass the Shockley‑Queisser limit of single‑junction silicon. Yet, mobile ions inherent to the perovskite layer introduce dynamic electrochemical activity that can destabilize the device and erode power conversion efficiency. Traditional modeling approaches treat carrier transport and ion migration separately, overlooking the feedback loops that arise when ions participate in redox reactions. Understanding this carrier‑ion‑electrochemical nexus is therefore critical for translating laboratory efficiencies into reliable, commercial‑grade modules. Consequently, integrating ion chemistry into device models becomes a prerequisite for accurate lifetime predictions.

The authors present a self‑consistent multi‑physics framework that simultaneously solves Poisson’s equation, drift‑diffusion carrier transport, ion drift‑diffusion, and Butler‑Volmer electrochemical kinetics. Simulations reveal that ionic reactions dramatically reshape both carrier and ion profiles, creating localized energy losses that directly depress open‑circuit voltage and fill factor. Under reverse‑bias scans, positively charged cations preferentially capture electrons, generating pronounced reaction‑induced losses; conversely, anions engage holes during forward scans, contributing to hysteresis and long‑term degradation. These mechanisms also partially offset band‑alignment penalties, highlighting a nuanced trade‑off between ionic compensation and efficiency loss.

From a commercial perspective, the model offers a predictive tool for engineering interface layers, ion‑blocking transport windows, and bias‑conditioning protocols that mitigate detrimental reactions while preserving beneficial ionic compensation. By quantifying the loss pathways, manufacturers can prioritize material compositions and encapsulation strategies that suppress cation‑electron and anion‑hole recombination events. The study therefore accelerates the roadmap toward stable, >30% efficient perovskite‑silicon tandems, positioning them as viable candidates for utility‑scale photovoltaics and reinforcing the sector’s push toward low‑cost, high‑yield solar deployment.