The researchers discussed this distinction, saying the the lithium carbonate shapes the graphene sheete, isolating them from each other and thereby preventing the formation of graphite. Then after the lithium carbonate is washed out with acid, only the 3-D graphene remains.
So far the researchers have only tested 3-D graphene's conductivity and performance in die-sensitized solar cells. Next they will optimize the process, at which point they will likely address the issues of longevity and stability.
The weekly reports of promising breakthroughs in solar cell technology tell me that we're looking at a technology in the midst of rapid change. It would appear that patience is needed before building any fabrication plants since just about when they come on-line is the date that they're obsolete. I can't wait until the technology stabilizes at a new economical price point and solar cells become a very competitive product for home power generation.