Sciencegeist: The Goblin Element

Originally posted November 23, 2010

No, I’m not going to talk about Harry Potter again

November 23, 2010


Cobalt is element 27, i.e. it has 27 protons in its nucleus. Cobalt may be my favorite element. It was instrumental in charting the course for our modern understanding of inorganic chemistry (the chemistry of non-carbon-based things … you know … the interesting stuff). Cobalt-based materials are used in the chemical industry for processing carbon monoxide (steam reforming to produce H2 and in the conversation of carbon monoxide and hydrogen into synthetic petroleum. And, materials made with cobalt are very likely going to play a key role in producing cheap solar energy (more on this later).

Metallic cobalt. (Image from wikipedia. Please see my important note on in the comment section.)

Cobalt gets its name from the German word Kobold, meaning goblin. Cobalt wasn’t discovered early enough to play a role in the development of alchemy. Although cobalt had been used for centuries to color glass blue (we all know cobalt from the special glass we use to look at an eclipse), attempted isolation of the cobalt from metal ores (which looked a lot like silver to the miners excavating it) didn’t occur until the late 1600′s. German miners named it Kobold ore (Goblin ore) because of all of the mischief it caused when they tried to refine it. As I mentioned above, ores containing cobalt looked a lot like silver. The miners would get really excited when they saw this. But, when they refined it, instead of getting beautiful, gleaming, expensive silver after smelting the ore, they were left with a pile of black powder (cobalt oxide). Rocks containing cobalt also tend to have arsenic in them too. Smelting of poisonous arsenic, as you may imagine, has much worse side-effects than just finding black powder in the place of silver.

Cobalt is a goblin. Mischevious, but very rewarding when treated right.

It turns out that the comparison of cobalt to a goblin is pretty spot on. As you may imagine, there are many examples of goblin lore in both German and Nordic folktales. (You can find a great compilation of many of Kobold folktales here.) But, the basic gist of all of these tales is: Goblins will be very good to the people that they live with as long as they are treated well. When a goblin feels that he is not treated well, his retribution is swift and stinging. A goblin requires consistent meals (biscuits, grits, bread, beer) in return for the magical gifts that they can provide (finding lost items, discovering an enemies secrets, gifts of gold and food). That’s a pretty good deal for the humans. But, as in many folktales, humans get lazy. They forget to feed their goblins. They forget to be grateful. They forget to pay attention. And, that’s when a goblin can get nasty. They play pranks, give their hosts diseases and disfigurements, bludgeon and dismember. So, the moral of this story is be nice to your goblin

Be attentive to your goblin (er … cobalt) and your cobalt will be good to you

As a postdoc, I did a little bit of research on the interaction of cobalt with proteins. My advisors and I had this really cool idea to start and stop the function of a protein by changing the charge state of a cobalt complex attached to that protein. It was a good idea … (alas it still is just an idea). You see, it was a side project. There were several projects I was working on. This one was just a pet. I wasn’t attentive enough to my cobalt. So, it played tricks on me. One protein-cobalt reaction gave me pink goo (this might actually be a good thing, but I wasn’t sure how to characterizing the goo without compromising it). In another reaction, the pH of my solution became too basic, and I was left with a vial of insoluble cobalt hydroxide. My goblins were repaying me for my lack of attention. Fortunately for me cobalt was never or harmful in its vengeance.

I stand in stark contrast to my good friend Jillian who is defending her thesis today. Jill not only tamed her cobalt. She got it to sit, roll over, and run a marathon barefooted! Jill’s project dealt with using cobalt as a catalyst to turn water into hydrogen fuel using sunlight as an energy source. Cobalt, in fact, has gotten a plenty of attention recently because many researchers see a lot of potential in using it in solar energy conversion devices. The Nocera group at MIT is using a sunlight and a cobalt catalyst to turn water into oxygen. The Peters group at Caltech and their research on solar hydrogen production was the inspiration for Jill’s thesis research with Harry Gray. Both the Peters and Nocera groups have come up with really fascinating materials and promising science. However, neither of their catalysts work well enough to make solar energy competitive in price with fossil fuels. Jill’s job was to ultimately figure out how the hydrogen-producing catalyst works so that other scientists can make it work better/more efficiently. Using a broad array of exotic-sounding techniques and chemicals: photoacids, flash-quench spectroscopy, pulsed radiolysis, etc she has tamed her cobalt catalyst. She has a full story on all of its workings. She gave her Kobold attention and her Kobold has been very good to her in return!

Moral of the story: watch out for cobalt, it can be benevolent or it can be vengeful


Congratulations to Jillian. Master of Goblins. PhD.