Structural, optical and photoelectrochemical studies on the nanodispersed titania

Gi Won Lee, So Yeon Bang, Chaehyeon Lee, Won Mok Kim, Donghwan Kim, Kyungkon Kim, Nam Gyu Park

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Nanodispersion of aggregated TiO 2 powders has been performed by microbead milling and its effect on photovoltaic performance has been investigated with dye-sensitized solar cell. Plasma-treated 30 μm-diameter zirconia beads are used to disperse the aggregated nanocrystalline TiO 2 powders in ethanolic medium. Particle size distribution, surface area, film morphology, porosity, transmittance and haze are investigated with different milling speed. Microbead milling leads to a reduction of particle size, narrow size distribution and increase of surface area. A slight crystal phase transformation from anatase to rutile is also observed after microbead milling. Optical property is found to be influenced by microbead milling speed, where transmittance increases and haze decreases with increasing milling speed. Compared with photovoltaic performance of dye-sensitized solar cells based on titania before and after microbead milling, overall conversion efficiency is substantially improved from 4.46% to 6.31% after microbead milling at 2490 rpm for 90 min, corresponding to 42% increment, which is mainly due to a noticeable increase in photocurrent density, associated with highly dispersed characteristics. According to the photocurrent and photovoltage transient spectroscopic study, time constant for electron transport is hardly affected, while that for recombination is slightly decreased due to the increased surface area by nanodispersion.

Original languageEnglish
Pages (from-to)900-906
Number of pages7
JournalCurrent Applied Physics
Volume9
Issue number5
DOIs
Publication statusPublished - 2009 Sep 1

    Fingerprint

Keywords

  • Aggregation
  • Dye-sensitized solar cell
  • Haze
  • Microbead milling
  • Nanodispersion

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy(all)

Cite this