Nanotubes

The science open people at reference 1 sent me this splendid picture of something called nanotube lanterns. Probably the work of the people at reference 2.

But despite the learned article at reference 3, I don't have a clue what these things are, beyond being small and tubular. Possibly with walls just one atom thick.

Reference 1: https://www.scienceopen.com/.

Reference 2: https://www.nanomanufacturing.eng.cam.ac.uk/.

Reference 3: https://en.wikipedia.org/wiki/Carbon_nanotube.