PMID- 20369868
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20100930
LR  - 20100630
IS  - 1520-5827 (Electronic)
IS  - 0743-7463 (Linking)
VI  - 26
IP  - 13
DP  - 2010 Jul 6
TI  - Wetting studies of hydrophilic-hydrophobic TiO2@SiO2 nanopatterns prepared by 
      photocatalytic decomposition.
PG  - 11330-6
LID - 10.1021/la1006583 [doi]
AB  - TiO(2)@SiO(2) nanopatterns were prepared with the evaporation-induced 
      self-assembly (EISA) technique. The material consists of an ultrathin 
      (approximately 2 nm) layer of titania with hexagonally ordered craters of roughly 
      30 nm in diameter, on a silica substrate. The open pore structure and high 
      homogeneity of the pattern makes these materials ideal for detailed wetting 
      studies. The nanopatterns were functionalized with a fluoroalkylsilane (FAS), 
      which attached on both titania and silica, resulting in a hydrophobic surface. By 
      irradiating the composite material with UV light for different lengths of time, 
      the hydrophilic/hydrophobic contrast in the nanopattern could be tuned. This is a 
      result of the very different photocatalytic properties of titania and silica. The 
      area fraction covered with FAS, f(FAS), as a function of UV irradiation time was 
      calculated from water contact angle measurements of the composite film and 
      corresponding reference samples, by using existing wetting models for 
      heterogeneous surfaces. The results were compared to area fractions derived from 
      X-ray photoelectron spectroscopy (XPS). f(FAS)-values determined from static 
      water contact angles gave the best agreement with XPS, while advancing and 
      receding contact angles overestimated and underestimated the f(FAS)-values, 
      respectively. The Cassie model gave a slightly better fit to the XPS data than 
      the Israelachivili model.
FAU - Jarn, Mikael
AU  - Jarn M
AD  - Center for Functional Materials, Laboratory of Physical Chemistry, Department of 
      Natural Sciences, Abo Akademi University, Porthansgatan 3-5, FI-20500 Finland.
FAU - Xu, Qian
AU  - Xu Q
FAU - Linden, Mika
AU  - Linden M
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Langmuir
JT  - Langmuir : the ACS journal of surfaces and colloids
JID - 9882736
EDAT- 2010/04/08 06:00
MHDA- 2010/04/08 06:01
CRDT- 2010/04/08 06:00
PHST- 2010/04/08 06:00 [entrez]
PHST- 2010/04/08 06:00 [pubmed]
PHST- 2010/04/08 06:01 [medline]
AID - 10.1021/la1006583 [doi]
PST - ppublish
SO  - Langmuir. 2010 Jul 6;26(13):11330-6. doi: 10.1021/la1006583.