Multi-layering of a nanopatterned TiO2 layer for highly efficient solid-state solar cells

Abstract

A facile process to prepare multi-layered nanopatterned photoanodes (MNPs) is presented with well-arrayed mesoporous inorganic oxide layers. The MNPs were prepared with multiple stacking of nanopatterned TiO 2 layers using a sacrificial polystyrene (PS)-thin film layer, which not only guided the stacking TiO 2 layer but also was removed completely by calcination without generating cracks. The prepared MNPs exhibited large enhancement of the light harvesting property by increasing the number of nanopatterned TiO 2 layers, through multiple reflection of the incident light from the periodic embedded channels formed between the nanopatterned layers. The photovoltaic efficiency was optimized with a 3-layered nanopatterned photoanode exhibiting a 73% J sc and a 65% power conversion efficiency enhancement compared with a cell with a flat TiO 2 layer for I 2 -free solid-state dye-sensitized solar cells.

Oxygen insensitive thiol–ene photo-click chemistry for direct imprint lithography of oxides

“…Abstraction of a hydrogen radical from the neighborhood thiol to this carbon radical accomplishes the hydrothiolation, while simultaneously propagating the chain reaction. 9,17 Fabrication of micro/nanostructures of oxides is of paramount importance in various applications including photoelectrochemical cells, 18 photovoltaic cells, 19 sensors, 20 and catalysis. 21 Several techniques including photolithography, 22,23 electron-beam lithography, 24,25 electro-hydrodynamic lithography, 26,27 direct write assembly, 28 selective surface wetting, 29 dip-pen nanolithography, 30,31 nanoimprint lithography (NIL) [32][33][34] among others 35,36 have been utilized towards fabrication of metal oxide micro/nanostructures.…”

Geometric Effect of Grating-Patterned Electrode for High Conversion Efficiency of Dye-Sensitized Solar Cells

“…4 The effect of filling factor and slanted angle of diffraction gratings on reflectance and the analysis of diffracted light: a The reflectance with respect to filling factor when refractive index of electrolyte is from 1.00 to 1.35. b The amount of two lights passing through electrode (bold yellow line) and electrolyte (bold blue line) on the condition of F = 0.1 or smaller than 0.1. c The destructive interference of two lights, the one passes through electrolyte (bold blue line) and the other propagates laterally at the interface region 3 and region 1 (bold red line) on the condition of F = 0.1 or smaller than 0.1. d The reflectance with respect to slanted angle when refractive index of electrolyte is from 1.00 to 1.35 (color figure online) Fig. 5 The reflectance according to wavelength with optimal grating (purple line), without grating (black line), with diffraction grating developed by Kim [23] and Na [24] (color figure online) of N-719 dye is around 925, 783 and 1975% compared to previous researches and without gratings.…”

“…Based on analysis of interference of diffracted light, the amount of destructive interference on the condition θ = 90° is greater than any other conditions. [23] and Na [24]. Due to the selective reflectance of the diffraction grating what we designed, the transparent characteristics of DSSC make them suitable for outdoor applications, particularly for use as building integrated photovoltaic devices, where power supplying device replace conventional building materials such as window glass.…”

“…However, the optimized design of the diffraction grating of the standard solar cells does not valid to the DSSCs systems due to the different selection of the electrode and the electrolyte. A recent study proposed the DSSC system that employs the diffraction grating to improve the conversion efficiency [23][24][25]. However, they only focused on the methods of fabricating diffraction gratings, not the optimal design of diffraction gratings.…”

Numerical Study of Complementary Nanostructures for Light Trapping in Colloidal Quantum Dot Solar Cells

“…Periodic nanostructured gratings have been extensively explored for light trapping in various types of thin-film solar cells and various silicon or metamaterial-based structures have been proposed, such as nanopillar, nanowire, nanohole, and pyramid arrays [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. The downside, however, is that these structures are difficult to fabricate due to their complicated structures or material compositions.…”