Stable anatase TiO₂ coating on quartz fibers by atomic layer deposition for photoactive light-scattering in dye-sensitized solar cells

Quartz fibers provide a unique high surface-area substrate suitable for conformal coating using atomic layer deposition (ALD), and are compatible with high temperature annealing. This paper shows that the quartz fiber composition stabilizes ALD TiO₂ in the anatase phase through TiO ₂-SiO₂ interface formation, even after annealing at 1050°C. When integrated into a dye-sensitized solar cell, the TiO ₂-coated quartz fiber mat improves light scattering performance. Results also confirm that annealing at high temperature is necessary for better photoactivity of ALD TiO₂, which highlights the significance of quartz fibers as a substrate. The ALD TiO₂ coating on quartz fibers also boosts dye adsorption and photocurrent response, pushing the overall efficiency of the dye-cells from 6.5 to 7.4%. The mechanisms for improved cell performance are confirmed using wavelength-dependent incident photon to current efficiency and diffuse light scattering results. The combination of ALD and thermal processing on quartz fibers may enable other device structures for energy conversion and catalytic reaction applications.