How Do Glow Sticks Work?
With no bulb or battery, glow sticks manage to give off a strong
light. So how exactly do glow sticks work? Glow stick light is
the result of a chemical reaction. Most glow sticks hold a
hydrogen peroxide solution and a solution containing phenyl
oxalate ester and a fluorescent dye. When the two compounds are
mixed, the hydrogen peroxide oxidizes the phenyl oxalate ester,
resulting in a chemical called phenol and an unstable acid
ester. The unstable compound decomposes, resulting in additional
phenol and a cyclic peroxy compound. The cyclic peroxy compound
then decomposes to carbon dioxide; this decomposition process
releases energy to the dye, and the electrons in the dye atoms
jump to a higher level, then fall back down, releasing energy in
the form of light.
The actual light stick is simply a form of housing the two
solutions. In the stick, the two solutions are kept in separate
chambers. The phenyl oxalate ester and dye solution fills most
of the glow stick, while the hydrogen peroxide solution is held
in a smaller glass vial within the middle of the stick. This is
why glow sticks must be bent to activate - bending the plastic
stick breaks the glass vial open, allowing the two solutions to
mix.
The glow stick can stay lit for hours, if enough compounds are
used. However, more commercial glow sticks are likely to last up
to 30 minutes. Also, heating the glow stick will cause it to
glow brighter, but it will also dim more quickly. Similarly,
cooling the stick will slow down the process and cause a dimmer
light to last much longer. Freezing a glow stick can cause the
light to last for several days, though it will eventually fade
out.
Although some websites offer information on how to make a glow
stick, this is discouraged unless a person has a background in
science and considerable training in chemical compounds. While
relatively safe, mixing the compounds incorrectly can lead to
inadvertent results, and the dye can harm clothing and other
fabrics.