Isn't DAF and skimmer already solved this ? The article does not goes in to details, but I reckon it's a oliophilic foam material instead of a rope or belt that

Isn't DAF and skimmer already solved this ? The article does not goes in to details, but I reckon it's a oliophilic foam material instead of a rope or belt that we usually use, thus increase contact area ? Edit: my bad, this article is about using nanoparticles to increase solar distillation efficiency.