Electron transport patterns in TiO2 nanotube arrays based dye-sensitized solar cells under frontside and backside illuminations

Po Tsung Hsiao, Yong Jin Liou, Hsisheng Teng

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

TiO2 nanotube arrays (NTA), of 17-37 μm in thickness, detached from anodic oxidized Ti foils were used as photoanodes for dye-sensitized solar cells (DSSCs). Photovoltaic measurements under frontside and backside illumination showed that frontside illumination geometry provided better cell performance than backside illumination did. A cell assembled with 30 μm thick NTA film produced the greatest photocurrent and light conversion efficiency. Despite an advantageous architecture for electron transport, electron trapping remained a limiting factor for both illumination geometries, due to the presence of crystal grains in the NTA walls. Intensity-modulated photocurrent spectroscopy (IMPS) analysis showed that electron transport in the front-illuminated cells comprises both trap-free and trap-limited diffusion modes, whereas electrons in the back-illuminated cells travel only by trap-limited diffusion. The trap-free diffusion mechanism determines front-illuminated cell performance. Electrochemical impedance spectroscopy analysis showed the front-illuminated NTA-based DSSCs have a charge collection efficiency of better than 90%, even at 30 μm NTA film thickness. Large crystal size results in low trap state density in the NTA film, and this effect may result in a more extensive trap-free diffusion zone in the films, which facilitates charge collection.

Original languageEnglish
Pages (from-to)15018-15024
Number of pages7
JournalJournal of Physical Chemistry C
Volume115
Issue number30
DOIs
Publication statusPublished - 2011 Aug 4

Fingerprint

Nanotubes
nanotubes
solar cells
Lighting
dyes
illumination
traps
cells
electrons
Photocurrents
photocurrents
Crystals
Geometry
Electrons
geometry
Electrochemical impedance spectroscopy
Metal foil
spectroscopy
travel
Conversion efficiency

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Energy(all)

Cite this

@article{14a9e3fadf3c4e18bbf7ba842d6ac538,
title = "Electron transport patterns in TiO2 nanotube arrays based dye-sensitized solar cells under frontside and backside illuminations",
abstract = "TiO2 nanotube arrays (NTA), of 17-37 μm in thickness, detached from anodic oxidized Ti foils were used as photoanodes for dye-sensitized solar cells (DSSCs). Photovoltaic measurements under frontside and backside illumination showed that frontside illumination geometry provided better cell performance than backside illumination did. A cell assembled with 30 μm thick NTA film produced the greatest photocurrent and light conversion efficiency. Despite an advantageous architecture for electron transport, electron trapping remained a limiting factor for both illumination geometries, due to the presence of crystal grains in the NTA walls. Intensity-modulated photocurrent spectroscopy (IMPS) analysis showed that electron transport in the front-illuminated cells comprises both trap-free and trap-limited diffusion modes, whereas electrons in the back-illuminated cells travel only by trap-limited diffusion. The trap-free diffusion mechanism determines front-illuminated cell performance. Electrochemical impedance spectroscopy analysis showed the front-illuminated NTA-based DSSCs have a charge collection efficiency of better than 90{\%}, even at 30 μm NTA film thickness. Large crystal size results in low trap state density in the NTA film, and this effect may result in a more extensive trap-free diffusion zone in the films, which facilitates charge collection.",
author = "Hsiao, {Po Tsung} and Liou, {Yong Jin} and Hsisheng Teng",
year = "2011",
month = "8",
day = "4",
doi = "10.1021/jp202681c",
language = "English",
volume = "115",
pages = "15018--15024",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "30",

}

Electron transport patterns in TiO2 nanotube arrays based dye-sensitized solar cells under frontside and backside illuminations. / Hsiao, Po Tsung; Liou, Yong Jin; Teng, Hsisheng.

In: Journal of Physical Chemistry C, Vol. 115, No. 30, 04.08.2011, p. 15018-15024.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Electron transport patterns in TiO2 nanotube arrays based dye-sensitized solar cells under frontside and backside illuminations

AU - Hsiao, Po Tsung

AU - Liou, Yong Jin

AU - Teng, Hsisheng

PY - 2011/8/4

Y1 - 2011/8/4

N2 - TiO2 nanotube arrays (NTA), of 17-37 μm in thickness, detached from anodic oxidized Ti foils were used as photoanodes for dye-sensitized solar cells (DSSCs). Photovoltaic measurements under frontside and backside illumination showed that frontside illumination geometry provided better cell performance than backside illumination did. A cell assembled with 30 μm thick NTA film produced the greatest photocurrent and light conversion efficiency. Despite an advantageous architecture for electron transport, electron trapping remained a limiting factor for both illumination geometries, due to the presence of crystal grains in the NTA walls. Intensity-modulated photocurrent spectroscopy (IMPS) analysis showed that electron transport in the front-illuminated cells comprises both trap-free and trap-limited diffusion modes, whereas electrons in the back-illuminated cells travel only by trap-limited diffusion. The trap-free diffusion mechanism determines front-illuminated cell performance. Electrochemical impedance spectroscopy analysis showed the front-illuminated NTA-based DSSCs have a charge collection efficiency of better than 90%, even at 30 μm NTA film thickness. Large crystal size results in low trap state density in the NTA film, and this effect may result in a more extensive trap-free diffusion zone in the films, which facilitates charge collection.

AB - TiO2 nanotube arrays (NTA), of 17-37 μm in thickness, detached from anodic oxidized Ti foils were used as photoanodes for dye-sensitized solar cells (DSSCs). Photovoltaic measurements under frontside and backside illumination showed that frontside illumination geometry provided better cell performance than backside illumination did. A cell assembled with 30 μm thick NTA film produced the greatest photocurrent and light conversion efficiency. Despite an advantageous architecture for electron transport, electron trapping remained a limiting factor for both illumination geometries, due to the presence of crystal grains in the NTA walls. Intensity-modulated photocurrent spectroscopy (IMPS) analysis showed that electron transport in the front-illuminated cells comprises both trap-free and trap-limited diffusion modes, whereas electrons in the back-illuminated cells travel only by trap-limited diffusion. The trap-free diffusion mechanism determines front-illuminated cell performance. Electrochemical impedance spectroscopy analysis showed the front-illuminated NTA-based DSSCs have a charge collection efficiency of better than 90%, even at 30 μm NTA film thickness. Large crystal size results in low trap state density in the NTA film, and this effect may result in a more extensive trap-free diffusion zone in the films, which facilitates charge collection.

UR - http://www.scopus.com/inward/record.url?scp=79961053419&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79961053419&partnerID=8YFLogxK

U2 - 10.1021/jp202681c

DO - 10.1021/jp202681c

M3 - Article

VL - 115

SP - 15018

EP - 15024

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 30

ER -