Scalable Fabrication of RGB-Color, Semi-Transparent DSSC Modules Enabled by a Printable Compact TiO₂ Blocking Layer

We report the development of a screen-printable compact TiO₂ blocking layer (sp-BL) optimized for semi-transparent dye-sensitized solar cell (DSSC) modules. The sp-BL enables uniform and reproducible film formation, effective interfacial contact, and suppressed interfacial recombination, offering improved photovoltaic performance and scalability compared to conventional blocking layers. Using the sp-BL along with tailored mesoporous TiO₂ and a screen-printed Pt counter electrode, large-area DSSC modules (100.8 cm²) were fabricated in red, green, and blue variants. These modules exhibited power conversion efficiencies (PCEs) ranging from 4.1 % to 7.0 %, average visible transmittance (AVT) values around 30 % and up to 52 % depending on design, and light utilization efficiency (LUEs) up to 2.1 %. The cell-to-module efficiency losses were limited to 11–16 %, confirming the effectiveness of the screen-printing strategy for scalable fabrication of color-tunable, semi-transparent DSSC modules suitable for building-integrated photovoltaic application.