Facile synthesis of GO@SnO2/TiO2 nanofibers and their behavior in photovoltaics

Abstract

Chemical doping is a widely-used strategy to improve the performance of TiO2 for the dye-sensitized solar cells (DSCs). However, the effect of two efficient dopants has been rarely investigated. We present the synthesis of GO@SnO2/TiO2 nanofibers (NFs) by a facile method using electrospinning and hydrothermal processes. The synthesized NFs are described in terms of morphology, crystallinity and chemistry through FESEM, TEM, HR-TEM, XRD, EDX, XPS, FT-IR and Raman spectra. As the results, the axial ratio and the average diameter of NFs decreased after the hydrothermal treatment and calcination process, respectively. The prepared Titania-based nanofibers have 81.82% anatase and 18.18% rutile-structure. The developed materials are applied as working electrodes of DSCs. The photovoltaic performances showed that the efficiency of the device employed GO@SnO2/TiO2 photoanode gave 5.41%, which was higher than those of cells fabricated with SnO2/TiO2 NFs (3.41%) and GO@TiO2 NFs (4.52%) photoanodes. The photovoltaic parameters such as Jsc, Voc, FF and Rct are calculated and found to be 11.19mAcm−2, 0.72V, 0.67 and 9.26Ω, respectively. The high photovoltaic response of DSC based of GO@SnO2/TiO2 NFs may be attributed to the large surface area of the NFs, and the low electron recombination. Furthermore, the start-stop switches of the cell devices with the developed photoanode affirmed the stability and photovoltaic performance of the cell.