TY - JOUR
T1 - Fabrication of nanoporous and hetero structure thin film via a layer-by-layer self assembly method for a gas sensor
AU - Kim, Jin Ho
AU - Kim, Sae Hoon
AU - Shiratori, Seimei
N1 - Funding Information:
This work was partially supported by Grant-in-Aid for the 21st Century COE program “KEIO Life Conjugate Chemistry” from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.
PY - 2004/9/13
Y1 - 2004/9/13
N2 - Nanoporous and hetero structure thin film consisted of weak polyelectrolytes and TiO2 nanoparticles was fabricated by the sequential depositions of oppositely charged solutions via a layer-by-layer self assembly (LBL-SA) method on a quartz crystal microbalance (QCM) at room temperature and then by an immersion in acidic water (pH 1.8) for 2min and neutral water for 10s subsequently. Because in this process, the ionic bonds of weak polyelectrolytes between poly(allylamine hydrochloride) and poly(acrylic acid) were broken, which contributed to separate the agglomerated TiO 2 nanoparticles in thin film. In order to measure the gas sensitivity of hetero structure thin film with a high surface area, the frequency shifts of a QCM were monitored as functions of the concentration of ammonia gas and relative humidity. The QCM immersed in acidic water showed larger frequency shifts than the QCM, without an immersion. As the concentration of gas and relative humidity were increased, the frequency shifts of a QCM were also increased gradually.
AB - Nanoporous and hetero structure thin film consisted of weak polyelectrolytes and TiO2 nanoparticles was fabricated by the sequential depositions of oppositely charged solutions via a layer-by-layer self assembly (LBL-SA) method on a quartz crystal microbalance (QCM) at room temperature and then by an immersion in acidic water (pH 1.8) for 2min and neutral water for 10s subsequently. Because in this process, the ionic bonds of weak polyelectrolytes between poly(allylamine hydrochloride) and poly(acrylic acid) were broken, which contributed to separate the agglomerated TiO 2 nanoparticles in thin film. In order to measure the gas sensitivity of hetero structure thin film with a high surface area, the frequency shifts of a QCM were monitored as functions of the concentration of ammonia gas and relative humidity. The QCM immersed in acidic water showed larger frequency shifts than the QCM, without an immersion. As the concentration of gas and relative humidity were increased, the frequency shifts of a QCM were also increased gradually.
KW - Gas sensor
KW - Layer-by-layer self assembly
KW - Polyelectrolyte
KW - Titanium dioxide
UR - http://www.scopus.com/inward/record.url?scp=4344573534&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=4344573534&partnerID=8YFLogxK
U2 - 10.1016/j.snb.2004.04.026
DO - 10.1016/j.snb.2004.04.026
M3 - Article
AN - SCOPUS:4344573534
VL - 102
SP - 241
EP - 247
JO - Sensors and Actuators B: Chemical
JF - Sensors and Actuators B: Chemical
SN - 0925-4005
IS - 2
ER -