Advances in dye sensitized solar cells: components, mechanisms, strategies and efficiency enhancement via rare earth doped phosphor integration

Dye-sensitised solar cells (DSSCs) combine colour/opacity tunability, simple low-temperature processing, and strong low-light performance, making them attractive for BIPV and indoor power. Their key bottlenecks are spectral mismatch (UV wasted and damaging; NIR under-utilised) and durability under UV, thermal & humidity stress, alongside interfacial recombination. This review focuses on a targeted solution: rare-earth (RE) enabled spectral tuning via down-conversion/down-shifting (DC/DS) and up-conversion (UC) phosphors. We cover two implementation routes (i) ex-situ optical interlayers/coatings and back-reflectors, and (ii) in-situ/self-phosphor photoanodes formed by RE-doping TiO 2 or ZnO linking photophysics to device outcomes. We link the underlying photophysics to device behaviour, focusing on UC/DC mechanisms (activator/host energy levels, sensitisation, phonon limits), materials and synthesis (solid-state, sol–gel, hydro/solvothermal, microwave; passivation/core–shell), and integration geometries (interlayers vs paste dispersions; refractive-index and porosity control; scattering length scales). Side-by-side quantitative benchmarks relate emission–absorption overlap, dopant loading, and device architecture to J sc , V oc , FF , PCE, and wavelength-resolved IPCE/EQE. Taken together, RE-phosphor-based photon management offers a practical path to measurable and durable efficiency gains in DSSCs, particularly for semi-transparent, flexible, and low-light applications.