50-layer pairs of PDADMA/PAA PEMs
were prepared on a Germanium
(Ge) FTIR crystal using an automated Carl Zeiss HMS slide stainer.
First, PDADMA and PAA solutions were prepared at 0.15 M and pH 3 to
match the final total concentration of the prepared PECs at a 1:1
mixing ratio. The Ge substrate was cleaned with acetone before deposition.
The first layer was deposited by dipping the Ge substrate in PDADMA
solution for 15 min, followed by three separate rinse steps for 2,
1, and 1 min in Milli-Q water at pH 3. The second layer was deposited
by dipping in the PAA solution, followed by three similar rinses.
These two steps were repeated a total of 50 times to form 50 layer-pairs.
The PEMs were dried under ambient conditions overnight before VT-FTIR
spectroscopy measurements.
The coated Ge FTIR crystal was fitted
in a custom-made sample stage from Harrick Scientific Products Inc.
connected to a Bruker Tensor II FTIR spectrometer. First, background
spectra of the bare Ge crystal were collected at 10 °C intervals
from 27 to 75 °C. FTIR spectra were recorded from 4000 to 600
cm–1 at a resolution of 2 cm–1 in the attenuated total reflectance (ATR) mode at each studied temperature
in triplicates.
were prepared on a Germanium
(Ge) FTIR crystal using an automated Carl Zeiss HMS slide stainer.
First, PDADMA and PAA solutions were prepared at 0.15 M and pH 3 to
match the final total concentration of the prepared PECs at a 1:1
mixing ratio. The Ge substrate was cleaned with acetone before deposition.
The first layer was deposited by dipping the Ge substrate in PDADMA
solution for 15 min, followed by three separate rinse steps for 2,
1, and 1 min in Milli-Q water at pH 3. The second layer was deposited
by dipping in the PAA solution, followed by three similar rinses.
These two steps were repeated a total of 50 times to form 50 layer-pairs.
The PEMs were dried under ambient conditions overnight before VT-FTIR
spectroscopy measurements.
The coated Ge FTIR crystal was fitted
in a custom-made sample stage from Harrick Scientific Products Inc.
connected to a Bruker Tensor II FTIR spectrometer. First, background
spectra of the bare Ge crystal were collected at 10 °C intervals
from 27 to 75 °C. FTIR spectra were recorded from 4000 to 600
cm–1 at a resolution of 2 cm–1 in the attenuated total reflectance (ATR) mode at each studied temperature
in triplicates.