UV management by luminescent down-shifting for efficient and stable photovoltaics

As emerging photovoltaics move from record efficiencies toward practical deployment, simultaneously improving power conversion efficiency and long-term stability has become a central challenge. UV spectral conversion has attracted growing interest as a photonic management strategy. In this review, we summarize recent progress in UV-to-visible luminescent down-shifting (LDS) materials for high-efficiency crystalline silicon, perovskite, and organic solar cells. We show that the primary role of LDS is to alleviate short-wavelength spectral mismatch and parasitic absorption while suppressing UV-induced degradation through spectral shifting. Accordingly, device performance depends not only on selective UV absorption, photoluminescence quantum yield, Stokes shift, reabsorption loss, and emission-external quantum efficiency matching, but also on long-term UV durability. Furthermore, we compare the advantages and limitations of rare-earth systems, quantum-dot systems, organic molecule/polymer systems, and multifunctional composites, and then examine the functions of external coatings, encapsulation-integrated layers, antireflection/light-trapping coupled structures, and buried-interface integration. Taken together, these advances suggest that future progress will rely on the development of integrable, manufacturable, and weather-resistant front-end photonic management layers that combine UV-to-visible conversion with antireflection, directional scattering, encapsulation barrier properties, and interface protection, thereby enabling concurrent improvements in both efficiency and stability.