Conveniently fabricated heterojunction ZnO/TiO2 electrodes using TiO2 nanotube arrays for dye-sensitized solar cells

Improving the Efficiency of Dye-Sensitized Solar Cells by Growing Longer ZnO Nanorods on TiO2 Photoanodes

“…In contrast, those parameters for the DSSC without ZnO decoration are 0.37 mA/cm 2 , 0.66 V, and 0.15%, respectively. The improved photovoltaic performance of DSSCs can be attributed to the following facts: (i) an energy barrier is formed at the TiO 2 /electrolyte interface to reduce the electron back recombination [3,4,[6][7][8][9][10]; (ii) the longer ZnO nanorods provide larger surface area for more dye adsorption; and (iii) the lower defect density in longer ZnO nanorods favors more efficient electron transport in the nanorods. More specifically, the enhancement in SC can be attributed to the larger surface area and the lower defect density in longer ZnO nanorods whilst the slight decrease in OC can be caused by the larger serial resistance in the longer ZnO nanorods.…”

“…Under illumination, the dye molecules adsorbed on TiO 2 are excited to their lowest unoccupied molecule orbitals with the result of released photoelectrons, and then the released photoelectrons are injected into the wide bandgap semiconductor TiO 2 [6][7][8][9]. Consequently the interface between TiO 2 and the electrolyte becomes critically important in improving the power conversion efficiency of the TiO 2 based DSSCs [6][7][8][9][10][11]. It is well recognized that a further increase in the power conversion efficiency has been limited by energy loss due to the recombination of electrons in the photoanode with the oxidized dye molecules or with the electron-accepting species in the electrolyte [10][11][12][13].…”

“…Consequently the interface between TiO 2 and the electrolyte becomes critically important in improving the power conversion efficiency of the TiO 2 based DSSCs [6][7][8][9][10][11]. It is well recognized that a further increase in the power conversion efficiency has been limited by energy loss due to the recombination of electrons in the photoanode with the oxidized dye molecules or with the electron-accepting species in the electrolyte [10][11][12][13]. In order to minimize the electron back transfer from TiO 2 to the redox electrolyte, vertically aligned ZnO nanorods are often applied to DSSCs as the blocking layer since they can form an energy barrier at the electrolyte/TiO 2 interface in addition to providing large surface area for dye adsorption and direct pathway for efficient electron transport from the electrolyte to the photoanode [3,4,6,7].…”

Nanoparticles of TiO2-ZnO Modified Polystyrene-Acrylonitrile Characterization Using Glassy Carbon Electrode

“…The results of the research were expanding their applications, as a photo-anode for photo-electrochemistry [7]. Use of ZnO/TiO 2 -Ti nanocomposite (NC) as a photo-anode electrode in solar cell increased electron transport, electron lifetime and dye absorption [8].…”

Visible light-driven photoelectrochemical water splitting on ZnO–TiO2 heterogeneous nanotube photoanodes

“…Nanoscaled zinc oxide particles with different amounts were coated on titanate nanotubes by Wang [32]. Some reports have shown that the ZnO-decorated TiO 2 nanotubes obtained by electrochemical deposition are much more efficient for dye-sensitized solar cells, and results showed that the photovoltaic efficiency of these cells was improved by more compared to DSSCs with as-prepared TiO 2 nanotubes [6,33,34]. Also recently, Xiao et al prepared ZnO nanorods (NRs)-decorated nanoporous-layer-covered TiO 2 nanotube array (ZnO NRs/NP-TNTAs nanocomposites), in which ZnO NRs were evenly distributed on the NP-TNTAs substrate, by two-step anodization route combined with an electrochemical deposition strategy.…”