Highly porous Ba3Ti4Nb4O21 perovskite nanofibers as photoanodes for quasi-solid state dye-sensitized solar cells

Abstract

Ternary oxides are considered promising electrode materials for light harvesting devices due to their optical and electronic properties that can be tuned by controlling their composition and doping ratio. Herein, a facile approach is demonstrated to fabricate ternary oxide perovskite nanofibers (NFs) and their investigation investigated as efficient electrode materials in dye-sensitized solar cells (DSSCs). The fabricated electrospun hexagonal perovskite-like (A3B8O21) nanofibers are made of several small single crystals that are connected together to several micrometers in length. Upon sintering to 650 ⁰C, highly porous perovskite nanofibers were obtained, which increased the dye adsorption capacity of the nanofibers and in turn resulted in higher photoconversion efficiency than the traditional nanotubes counterparts. The crystallinity, chemical, and thermal characteristics of the fabricated NFs were investigated using XRD, SEM, TEM, and TGA analyses. Moreover, Brunauer–Emmett–Teller (BET) measurements were used to evaluate the effect of annealing temperature on the pore size and the overall surface area of the NFs. The fabricated nanofibers were used to construct full solar cell devices, revealing enhancement in the overall performance as indicated via the photocurrent-voltage curves. This enhancement is mainly related to the higher adsorption rate of the dye on the nanofibers surface. Highly porous electrospun nanofibers are good platforms that should be useful for the future development of solar cell devices.