Design of an efficient photoanode for dye-sensitized solar cells using electrospun one-dimensional GO/N-doped nanocomposite SnO₂/TiO₂

Highlights: • GO &N@SnO₂/TiO₂ NFs are synthesized via facile two steps. • The novel NFs photoanode exhibit high dye-loading ability; 2.164 × 10⁻⁷ mol/cm². • Prolonged electron lifetime (20.09 ms) is due to reduced charge recombination. • High power conversion efficiency was achieved; 6.18%. - Abstract: This study presents the combination of N, graphene oxide (GO) and SnO₂ as efficient dopants into TiO₂ nanofibers (NFs) photoanode substrate for highly efficient dye-sensitized solar cells (DSCs). The developed NFs are synthesized by electrospinning and hydrothermal processes and characterized by FESEM, TEM, XPS, FT-IR, Raman and EDX-studies. The formation of short NFs is confirmed through FESEM and TEM measurements. As the results, the major crystal structure of TiO₂ in the prepared NFs has anatase (85.23%) and rutile-structure (14.67%). XPS and EDX studies affirm that the material has Ti, O, Sn, N and C elements. In addition, FT-IR and Raman spectra give an indication about the GO-content. Typically, the DSC based on the novel NFs shows 6.18% efficiency. The J_sc, V_oc, FF and R_ct are estimated and found to be 10.32 mA cm⁻², 0.825 V, 0.73 and 21.66 Ω, respectively. The high-power efficiency is contributed by three reasons. The first one is the high dye-loading (2.16 × 10⁻⁷ mol cm⁻²). The second reason is the enhanced charge transfer and decreasing of the electrons/holes recombination through formation of wide band-gap oxide (3.246 eV). Finally, the third one is GO-doping which may create new routes for the electron transfer in working electrode layer.