Enhanced performance of ZnO-based dye-sensitized solar cells using TiO₂/graphene nanocomposite compact layer

Abstract

The applications of TiO2/graphene nanocomposite as a compact layer for ZnO-based dye-sensitized solar cell (DSSC) have been studied. It was shown that the role of bifunctional graphene flakes in TiO2 compact layer not only suppressed the electron recombination between indium-doped tin oxide and electrolyte, but also reduced the resistance of compact layer. In addition, compared to typical compact layers, TiO2/graphene nanocomposite without blocking effect in optical transmittance could further boost the power conversion efficiency in DSSC. TiO2/graphene nanocomposite was demonstrated the potential to be an alternative of compact layer to typical dense TiO2 for ZnO-based DSSCs.

Influences of sintering temperature on low-cost carbon paste based counter electrodes for dye-sensitized solar cells

“…The typical Raman spectra were the G band (1584 cm −1 ) ascribed to the sp 2 bond and D band (1322 cm −1 ) assigned to the presence of crystal defects, amorphous carbon and dangling bonds. 12,25) After sintering at 300 °C, the D=G ratios were decreased from 1.013 to 0.935. Similarly, it can be reasonably attributed to the reduced density of the defects within the carbon paste.…”

Direct formation of transfer-free graphene as current spreading layers on n-ZnO nanorods/p-GaN light-emitting diodes

“…In the figure, two pronounced peaks at 1580 and 2690 cm −1 are clearly identified as the G and 2D peaks, respectively. 9,27) The ratio of the integrated intensities of the 2D and G features, I 2D =I G , is only 0.42, which is much lower than that of the typical single-layer graphene, 1.3. 27) Thus, it is reasonable to infer that the graphene film on our ZnO NRs was composed of a few layers.…”

“…2,4,5) Additionally, compared with other wide-bandgap semiconductors, one of the advantages of ZnO is that various techniques have been reported for creating either well-aligned or randomly distributed ZnO-based nanostructures, e.g., sputtering, evaporation, sol-gel method, and hydrothermal method. 4,[6][7][8][9][10][11] Among them, one-dimensional nanostructured arrays, such as ZnO nanorods (NRs), can serve as optical waveguides owing to the gradient variation in refractive index, and the simplicity and reliability of the nanostructure enhance the light extraction efficiency of the LED since no additional lenses or rigid reflectors are required. 12) In general, p-n junction diodes are essential building blocks for ZnO-based LEDs, and yet, the fabrication of stable and reproducible p-type ZnO remains challenging.…”

Zinc oxide/graphene nanocomposite as efficient photoelectrode in dye‐sensitized solar cells: Recent advances and future outlook

“…According to the report by Huang and co-workers, the graphene/ZnO-nanoparticle bilayer structure has been utilized as a photoelectrode, which helps in enhancing the performance of DSSCs. 53 According to the experimental demonstration by Kilic and Turkdogan, when graphene is fabricated using 3D ZnO as a photoelectrode, it enhances the charge transfer of DSSCs. It, therefore, improves the efficiency of the device.…”

“…It is cost‐effective and efficient to be used in DSSCs, and thus, their performance has a constructive effect. According to the report by Huang and co‐workers, the graphene/ZnO‐nanoparticle bilayer structure has been utilized as a photoelectrode, which helps in enhancing the performance of DSSCs 53 …”