Greg, please reread the article, you missed the last paragraphs, apparently:
"In an article published in Nature Communications this week, the University of Manchester team shows that it is possible to tightly close those nanocapillaries using simple chemical treatments, which makes graphene films even stronger mechanically as well as completely impermeable to everything: gases, liquids or strong chemicals. For example, the researchers demonstrate that glassware or copper plates covered with graphene paint can be used as containers for strongly corrosive acids.
The exceptional barrier properties of graphene paint have already attracted interest from many companies who now collaborate with The University of Manchester on development of new protective and anticorrosion coatings.
Dr Nair said “Graphene paint has a good chance to become a truly revolutionary product for industries that deal with any kind of protection either from air, weather elements or corrosive chemicals. Those include, for example, medical, electronics and nuclear industry or even shipbuilding, to name but the few.”"
Nevertheless, out of curiosity, I look in Calder's 'Boatowners Electrical and Mechanical Manual,' 3d edition, page 199, Table 5-1 Galvanic Series of Metals in Seawater, and note that the most noble/passive listed is.... graphite.
BTW, and what about the copper in your bottom paint right now?
Thanks for the catch. I initially read it as the chemical treatment only being impervious against acids/corrosives/ect. But on second reading I think you are correct and the chemical treatment is also impermeable against water.
I this is correct then I think there could be a real application for the marine industry.
Like I said before however I would still be worried about conductivity. Graphene is a much better conductor than copper (in its elemental form), in fact it is the best room temprature conductor know to man. Controlling this will be a serious issue not that it isn't solvable, but it raises some real concerns to me.
The copper oxide used in bottom paint while made from copper is a semi-conductor with much lower conductivity than elemental copper. Even so it has been known to cause problems with aluminium hulls and running gear.
Graphene also has the problem that it is at the very high end of the galvanic chart. Which means that it will create a high potential galvanic circuit with just about anything except for titanium and carbon fiber. Even with stainless steel there is enough of a potential difference to cause galvanic issues.
Again all of these properties may be overcome with proper engineering, build, and application characteristics, but in a world where we still can't get boat builders to mount deck hardware without exposing core I have doubts that it will work.
Edit: it actually may be an easy application in a solid carbon fiber hull with titanium fittings. Since they all have the same (roughly) galvanic potential). This would result in a boat that just needs a few things properly protected (engines... And don't think about aluminium water tanks). But otherwise may not be such a difficult fit.
Graphene is fairly malleable in lots of ways, including conductivity, according to the things I'm reading (recent engineering 'tech watch' journals). I expect that in the near future, not unlike the way described in the article cited above, chemical manipulation will change other characteristics and allow it to be less or non conductive