Discovery of Boron
Boron compounds such as borax (sodium tetraborate, Na2B4O7·10H2O) have been known and used by ancient cultures for thousands of years. Borax’s name comes from the Arabic buraq, meaning “white.”
Boron was first partially isolated in 1808 by French chemists Joseph L. Gay-Lussac and L. J. Thénard and independently by Sir Humphry Davy in London. Gay-Lussac & Thénard reacted boric acid with magnesium or sodium to yield boron, a gray solid. They believed it shared characteristics with sulfur and phosphorus and named it bore.
Davy first tried to produce boron by electrolysis of boric acid, but was not satisfied with the results.
He enjoyed greater success reacting boric acid with potassium in a hydrogen atmosphere.
The result was a powdery substance.
Davy commented the substance was, “of the darkest shades of olive. It is opake, very friable, and its powder does not scratch glass.” After carrying out a number of chemical reactions to verify the uniqueness of the substance, Davy wrote, “there is strong reason to consider the boracic basis as metallic in nature, and I venture to propose for it the name of boracium.”
Neither party had, in fact, produced pure boron. Their samples were only about 60% pure.
In 1909, American chemist Ezekiel Weintraub was able to produce 99% pure boron, by reducing boron halides with hydrogen.
Almost a century later, in 2004, Jiuhua Chen and Vladimir L. Solozhenko produced a new form of boron, but were uncertain of its structure.
In 2009, a team led by Artem Oganov was able to demonstrate the new form of boron contains two structures, B12 icosohedra and B2 pairs. Gamma-boron, as it has been called, is almost as hard as diamond and more heat-resistant than diamond.
Talking about boron’s part metal, part non-metal properties, Oganov said, “Boron is a truly schizophrenic element. It’s an element of complete frustration. It doesn’t know what it wants to do. The outcome is something horribly complicated.”
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