Making phosphor at home
Phosphor - a substance capable of converting the energy it absorbs into light radiation. The color of the glow can be different and depends on the light filter applied to the surface of the phosphor or its impurity. Photo phosphor is a powder that has the property of glowing in the dark after being exposed to natural or artificial light.
To make the phosphor we need pine concentrate and boric acid.
We need to buy not “pine extract” at the pharmacy, but “pine concentrate”, because it contains a bright yellow dye, tartrazine (E102). The top pair of blue balls in its molecule is a chromophore (capable of receiving and emitting light) group -N=N- of two nitrogen atoms connected by a double bond. This ability is due to the fact that the -N=N- fragment can be in two positions and the transition energy between them is absorbed/emitted in the form of light.
In addition, this group is connected on one side to a benzene ring of six carbon atoms, and on the other side to a nitrogen-carbon ring and another benzene ring.This chain is a kind of corridor in which electrons can “run”. The permissible energies of such a run and
determine the color of the radiation.
Despite the fact that we understand how the dye molecule works, it is not yet obvious how it forms a phosphor - a molecular photobattery - with boric acid. Do it yourself and experiment.
Pour (or pour if you bought liquid) pine concentrate into a glass.
Pour in a little water to create an aqueous solution of tartrazine.
Pour boric acid into a spoon
Wet with dye solution
Stir to wet all the acid.
Boil until it reaches this state. We pierce the resulting bubbles with something sharp to ensure good heating of the entire mixture.
Cool, add more dye solution and boil the melt again. You will get a homogeneous yellow substance.
This is a phosphor! Use flash on it:
You can grind it into powder and apply it somewhere, add it to other substances and even to water.
Melting boric acid with solutions of other dyes - rhodamine and paste from blue gel pens also produced a phosphor, but of much worse quality. The big disadvantage of this method of preparing phosphor is the very short glow duration.
Also this phosphor glows well in ultraviolet radiation.
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