Evaluation of Fractal Structured Dye-Sensitized Solar Cells Made by Fused Transparent Filament Fabrication

Flexible dye-sensitized solar cells (DSSCs) offer several benefits in terms of cheap fabrication, mass production, lightweight, and, finally, conforming to uneven surfaces. However, these cells are mainly fabricated using commercially polymer substrates with limited functional properties. DSSCs performance is highly influenced by the dye adsorbent capability of nano-crystalline oxide semiconductors (TiO2), which require a large surface area, and this can be achieved by developing texture or microstructures on substrates. Further, texture-based substrates reduced the optical reflection, increased the optical path of light, and trapped large amounts of light. Different transparent filaments are used to print flexible substrates that possess high transparency using a versatile fused filament fabrication. Facile laser-engraved fractal textures are developed on printed polymer substrates, which act as photoanodes and counter electrodes. The maximum attained power conversion efficiency and short-circuit current density (Jsc) are 3.90% and 9.34 mA/cm2, respectively, for fractal anode-fractal cathode based DSSCs, which are 82.2% and 47.7%, respectively, higher than as-printed anode- as-printed cathode-based DSSCs.