PeroSeminar | 30 July 2026

Perovskite/silicon tandem solar cells are regarded as the most promising next-generation photovoltaic technology to break the efficiency limit of single-junction silicon cells. However, intrinsic ion migration (halide migration, vacancy-driven ion diffusion, and interfacial ion accumulation) remains the dominant source of intrinsic instability, causing lattice distortion, accelerated defect propagation, current mismatch, phase segregation, and long-term performance degradation in both 2-terminal (2T) and 4-terminal (4T) tandem configurations. Compared with single perovskite devices, tandem structures suffer more severe ionic deterioration due to complex interfacial electric field distribution, multilayer stacking stress, and cross-layer ion diffusion between the perovskite top cell and textured silicon bottom cell. This seminar systematically analyzes the fundamental mechanisms of ion migration-induced intrinsic failure in large-area tandem fabrication and operational aging. It further summarizes effective suppression strategies including bulk crystal engineering, interfacial passivation, dielectric gradient modification, defect vacancy healing, and optimized deposition protocols. The study clarifies configuration-specific instability differences between 2T and 4T tandem architectures and provides targeted solutions to restrict ionic diffusion channels, raise ion migration activation energy, and eliminate field-driven ion accumulation. This work offers a reliable technical roadmap to resolve intrinsic instability bottlenecks and accelerate the commercialization of high-stability, high-efficiency perovskite/silicon tandem solar modules.