There has been a lot of discussion about the lack of commercial applications of graphene, and the reason may be that much of what has been sold as graphene isn’t.
A recent paper in Natureconcluded that:
. . .As one can clearly see, the majority of the companies are producing less than 10% graphene content and no company is currently producing above 50% graphene content. This result may come as a surprise given the widely advertised graphene “fever” of the last decade. However, it also helps to understand why graphene applications are not commonplace yet.
Weirdly enough it turns out that most people attempting to make something out of graphene were actually dumping a load of carbon black or pencil lead into their composites, although paying top dollar for the privilege of using a cheap and widely understood material.
It is worth noting that the Nature paper didn’t survey every company claiming to produce graphene, so there may have been some conscious or unconscious bias in selecting the sample size. I’ve certainly come across materials that is well over the claimed 50% maximum.
There is nothing new in this. Carbon nanotubes had similar problems, with much of what was sold as the wonder material being a variety of assorted carbon filaments. For most applications the cheap and ‘not quite nano’ nanotubes worked fine, and anything that required the good stuff was automatically uneconomic. Last time I looked 99.9% pure semiconducting or metallic SWNTs were still almost half a million dollars a kilo.
Academics who know the difference between single layer graphene, multilayer graphene and a lump of graphite, are rightly outraged both by the lack of standards and the fact that nobody seems to care. Companies buying bags of black powder of dubious provenance need to invest in quality control or change suppliers.