Kim et al. created a sensitive, inexpensive, selective colorimeter sensor array by printing 10 indicators on PET film to detect toxic industrial gases (ammonia, methylamine, trimethylamine, and hydrazine). The colorimetric ink becomes stabilized on the substrate via solvent evaporation and a sol-gel mechanism. here they used the printing approach because the drop-casting method has numerous drawbacks: it is impossible to control the thickness, width, and form of each spot. in addition, depending on the chemical composition of the solution, the substrate, and the index, the coffee ring effect may be created all through drying to create a non-uniform spot. The effect of the coffee ring is because of the thickness of the colorimetric spot implemented to the substrate, and thickness is a critical element related to the initial color value and the gas sensitivity. here, a colorimetric spot can be controlled on a substrate within the preferred shape and thickness and can offer the basis for mass production. similarly, the manufacturing of sensors using the printing approach can produce massive quantities of chips at a low cost and in a short time. external light sources make it hard for the CMOS image sensor to detect great color changes that lead to designing the structure of the detector to minimize them. this structure permits sensitive detection of small color changes of the colorimetric array, and the gas detection results additionally can be monitored in real-time using a smartphone and central control machine through wireless transmission.
Kim et al. created a sensitive, inexpensive, selective
colorimeter
sensor array by printing 10 indicators on PET film to detect toxic industrial gases (ammonia,
methylamine
,
trimethylamine
, and
hydrazine
). The colorimetric ink becomes stabilized on the substrate via solvent evaporation and a sol-gel mechanism.
here
they
used
the printing approach
because
the drop-casting method has numerous drawbacks: it is impossible to control the
thickness
, width, and form of each
spot
.
in
addition, depending on the chemical composition of the solution, the substrate, and the index, the coffee ring effect may
be created
all through drying to create a non-uniform
spot
. The effect of the coffee ring is
because
of the
thickness
of the colorimetric
spot
implemented to the substrate, and
thickness
is a critical element related to the initial color value and the gas sensitivity.
here
, a colorimetric
spot
can
be controlled
on a substrate within the preferred shape and
thickness
and can offer the basis for mass production.
similarly
, the manufacturing of sensors using the printing approach can produce massive quantities of chips at a low cost and in a short time.
external
light sources
make
it
hard
for the CMOS image sensor to detect great color
changes
that lead to designing the structure of the detector to minimize them.
this
structure permits sensitive detection of
small
color
changes
of the colorimetric array, and the gas detection results
additionally
can
be monitored
in real-time using a smartphone and central control machine through wireless transmission.