A new form of gold, almost as light as air | Hacker News Reader

A new form of gold, almost as light as air

ethz.ch

64 pointsawqrre11 comments

So-called gold aerogel: 98 parts air, two parts gold and milk protein fibrils. A novel drying technique, using carbon dioxide, produces the homogeneous gold structure. Advantages: lighter weight, smaller material requirement, and porous structure.

What is the novel drying process? I can't proxy in to my uni on my phone so i cant read the full paper but the article doesnt seem to mention a new drying technique. Aerogels have been made using super critical CO2 for decades now (for example, as the space shuttle reentry tiles covering the entire spacecraft) and many interesting variants have been made using this technique including carbon aerogels which have a mind-boggling capacitance, on the order of 5 Farads per cubic centimeter.

I also believe gold/nanoparticle aerogels have been made before (difficult to find citation now), although this is the first time I've seen anyone use protein fibers.

Thank you; it seems I may have misunderstood. From the article, "The method chosen, in which the gold particles are crystallised directly during manufacture of the aerogel protein structure (and not, for example, added to an existing scaffold) is new. The method's biggest advantage is that it makes it easy to obtain a homogeneous gold aerogel, perfectly mimicking gold alloys."

The paragraph, on drying, preceded the above text. Hope this helps.

Applications aside from jewelry?

Article says pressure sensors, and also to efficiently act as a catalyst in chemical reactions requiring gold - Admittedly I'm not sure why this form of gold is superior as a catalyst.

Catalysts are not consumed. The effect is dependent on contact, so like the platinum in a catalytic converter the goal is surface area at minimum cost.

Aerogels have enormous surface area compared to their volume and chemical reactions are all about the amount of surface area engaging in the reaction.

That does imply that the gold is porous, and not made up out of chambers.

Actually, jewellery is one area this isn't useful. The end product is far too soft and would be damaged.

Would porous gold be able to store a liquid, such as latinum?

You made me learn that latinum is a silvery liquid.

I'm having a lot of fun reading this article in my head in a faux Swiss/German accent. Love the phrasing :)

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