Boron reactivity?

Quote: Originally posted by zts16

Really most boron compounds are a fair bit less interesting than elemental boron.

That's what you think zts16 but I beg to differ. Heating a mixture of B and Mg in my kiln under Argon (in quartz tube) was an experiment to make Magnesium diboride. You should look up it's superconducting properties.

http://en.wikipedia.org/wiki/Magnesium_diboride

Quoting "Its superconductivity was discovered by the group of Akimitsu in 2001.[1] Its critical temperature (Tc) of 39 K (−234 °C; −389 °F) is the highest amongst conventional superconductors. This material was first synthesized and its structure confirmed in 1953,[2] but its superconducting properties were not discovered until 2001.[3]

Though generally believed to be a conventional (phonon-mediated) superconductor, it is a rather unusual one. Its electronic structure is such that there exist two types of electrons at the Fermi level with widely differing behaviours, one of them (sigma-bonding) being much more strongly superconducting than the other (pi-bonding). This is at odds with usual theories of phonon-mediated superconductivity which assume that all electrons behave in the same manner. Theoretical understanding of the properties of MgB2 has almost been achieved with two energy gaps. In 2001 it was regarded as behaving more like a metallic than a cuprate superconductor."

"Magnesium diboride can be synthesized by several routes. The simplest is by high temperature reaction between boron and magnesium powders.[4] Formation begins at 650 °C; however, since magnesium metal melts at 652 °C, the reaction mechanism is considered to be moderated by magnesium vapor diffusion across boron grain boundaries. At conventional reaction temperatures, sintering is minimal, although enough grain recrystallization occurs to permit Josephson quantum tunneling between grains.

Superconducting magnesium diboride wire can be produced through the powder-in-tube (PIT) process. In the in situ variant, a mixture of boron and magnesium is poured into a metal tube, which is reduced in diameter by conventional wire drawing. The wire is then heated to the reaction temperature to form MgB2 inside. In the ex situ variant, the tube is filled with MgB2 powder, reduced in diameter, and sintered at 800 to 1000 °C. In both cases, later hot isostatic pressing at approximately 950 °C further improves the properties.

In 2003, a new and easy in situ technique for the synthesis of MgB2 was presented by Giunchi et al. (Edison S.p.A.).[5] This new technique employs reactive liquid infiltration of magnesium inside a granular preform of boron powders and was called Mg-RLI technique. The method allowed to manufacture both high density (more than 90% of the theoretical density for MgB2) bulk materials and special hollow fibers. This method is an exact of similar melt growth based methods such as the Infiltration and Growth Processing method used to fabricate bulk YBCO superconductors where the non-superconducting Y2Ba1Cu1O5 is used as granular preform inside which YBCO based liquid phases are infiltrated to make superconductive YBCO bulk. This method has been copied and adapted for MgB2 superconductor and rebranded as reactive Mg Liquid Infiltration. The process of Reactive Mg Liquid Infiltration in a boron preform to obtain MgB2 has been a subject of patent applications by Edison S.p.A. (Italy)."

All in all I think this is a very interesting substance.

http://arxiv.org/abs/cond-mat/0212543

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I should expand on my thoughts. From wiki: "Its critical temperature (Tc) of 39 K (−234 °C; −389 °F) is the highest amongst conventional superconductors." Getting down to −234 °C is beyond my budget. Yet some high TC properties look possible with this actually quite odd chemical (MgB2). Compare its structure to a high TC Cuprate structure.



What I have been experimenting with is trying to create many varieties in the kiln of MgB2 doped with various elements typical in the Cuprate example (as well as some other known high TC materials). Obviously with a goal in mind of a new high TC material with a TC closer to standard conditions than have thus far been created.

In any case I just thought I would point out by example that Boron is possibly not as 'boring' as you suggested.


[Edited on 6-29-2014 by IrC]

Quote: Originally posted by IrC

I should expand on my thoughts. From wiki: "Its critical temperature (Tc) of 39 K (−234 °C; −389 °F) is the highest amongst conventional superconductors." Getting down to −234 °C is beyond my budget. Yet some high TC properties look possible with this actually quite odd chemical (MgB2). Compare its structure to a high TC Cuprate structure. What I have been experimenting with is trying to create many varieties in the kiln of MgB2 doped with various elements typical in the Cuprate example (as well as some other known high TC materials). Obviously with a goal in mind of a new high TC material with a TC closer to standard conditions than have thus far been created. [Edited on 6-29-2014 by IrC]

Quote: Originally posted by The Volatile Chemist

You could always try it. It seems to me it would be a bit easier to make - Aluminum melts a bit easier. Hopefully the reaction temperature wouldn't be too high...