TY - JOUR
T1 - Rapid, simple method for determining the porosity of mesoporous TiO2 films using a quartz crystal microbalance (QCM)
AU - Mills, Andrew
AU - Burns, Luke
AU - O'Rourke, Christopher
AU - Madsen, Henrik
PY - 2016/1
Y1 - 2016/1
N2 - Two different mesoporous films of TiO2 were coated onto a QCM disc and fired at 450o
C for 30
min. The first film was derived from a sol-gel paste that was popular in the early days of dye-sensitised
solar cell, i.e. dssc, research, a TiO2(sg) film. The other was a commercial colloidal paste used to make
examples of the current dssc cell; a TiO2(ds) film. A QCM was used to determine the mass of the TiO2
film deposited on each disc and the increase in the mass of the film when immersed in water/glycerol
solutions with wt% values spanning the range 0-70%. The results of this work reveal that with both
TiO2 mesoporous films the solution fills the film's pores and acts as a rigid mass, thereby allowing the
porosity of each film to be calculated as: 59.1% and 71.6% for the TiO2(sg) and TiO2(ds) films,
respectively. These results, coupled with surface area data, allowed the pore radii of the two films to
be calculated as: 9.6 and 17.8 nm, respectively. This method is then simplified further, to just a few
frequency measurements in water and only air to reveal the same porosity values. The value of the
latter ‘one point’ method for making porosity measurements is discussed briefly.
AB - Two different mesoporous films of TiO2 were coated onto a QCM disc and fired at 450o
C for 30
min. The first film was derived from a sol-gel paste that was popular in the early days of dye-sensitised
solar cell, i.e. dssc, research, a TiO2(sg) film. The other was a commercial colloidal paste used to make
examples of the current dssc cell; a TiO2(ds) film. A QCM was used to determine the mass of the TiO2
film deposited on each disc and the increase in the mass of the film when immersed in water/glycerol
solutions with wt% values spanning the range 0-70%. The results of this work reveal that with both
TiO2 mesoporous films the solution fills the film's pores and acts as a rigid mass, thereby allowing the
porosity of each film to be calculated as: 59.1% and 71.6% for the TiO2(sg) and TiO2(ds) films,
respectively. These results, coupled with surface area data, allowed the pore radii of the two films to
be calculated as: 9.6 and 17.8 nm, respectively. This method is then simplified further, to just a few
frequency measurements in water and only air to reveal the same porosity values. The value of the
latter ‘one point’ method for making porosity measurements is discussed briefly.
U2 - 10.1016/j.solmat.2015.08.019
DO - 10.1016/j.solmat.2015.08.019
M3 - Article
SN - 0927-0248
VL - 144
SP - 78
EP - 83
JO - Solar Energy Materials & Solar Cells
JF - Solar Energy Materials & Solar Cells
ER -