High Efficiency Dye-Sensitized Solar Cells Based on Hierarchically Structured Nanotubes

Abstract

Dye-sensitized solar cells (DSSCs) based on hierarchically structured TiO(2) nanotubes prepared by a facile combination of two-step electrochemical anodization with a hydrothermal process exhibited remarkable performance. Vertically oriented, smooth TiO(2) nanotube arrays fabricated by a two-step anodic oxidation were subjected to hydrothermal treatment, thereby creating advantageous roughness on the TiO(2) nanotube surface (i.e., forming hierarchically structured nanotube arrays-nanoscopic tubes composed of a large number of nanoparticles on the surface) that led to an increased dye loading. Subsequently, these nanotubes were exploited to produce DSSCs in a backside illumination mode, yielding a significantly high power conversion efficiency, of 7.12%, which was further increased to 7.75% upon exposure to O(2) plasma.

Graphene-wrapped hierarchical TiO2 nanoflower composites with enhanced photocatalytic performance

“…[89][90][91] TiO2, and photocatalytic materials in general, can also be doped in order to change the band structure of the semiconductor material. Figure 10: Various hierarchical morphologies of TiO2 based on reaction temperature.…”

Maximizing omnidirectional light harvesting in metal oxide hyperbranched array architectures

“…1D nanostructures have been viewed as an ideal scaffold to composite with other homogeneous or heterogeneous structures such as nanoparticles (NPs), NRs, nanosheets (NSs), nanotubes and so on in order to ensure high surface area, reinforce light scattering and trapping and suppress unexpected back reaction (charge recombination) [30][31][32][33] . In particular, 2D NSs have been regarded as promising nano-components that exhibit bifunctional properties of both large surface area for dye adsorption and relatively direct pathways for the transportation of electrons to the electrode [34][35][36] .…”

TiO 2 nanorod-based photoelectrodes for dye solar cells with tunable morphological features

“…[20,21] However, modest PCE values have been reported 5 to date, mainly because of the reduced internal surface area offered by photoanodes which employ nanorods or nanowires with a mean size larger than 100 nm [12,22,23] and/or the severe degradation of the original structural morphological features of the selected anisotropic TiO2 nanocrystals upon sintering. [11,15,16] Hence, the real challenge is to design and fabricate a nanostructured photoanode which simultaneously 10 has a large surface area to absorb more dye molecules, efficient light scattering ability and fast electron transport (as represented in the sketch shown in Figure 1).…”