Graphite is supposed to be layers of graphene so the first natural question when thinking about how to use graphene is, why doesn't graphite have such amazing properties, however.. I think graphite probably has a lot of imperfections and maybe it's just zones that have layers of graphene, and in-between each zone the grain boundary makes the bulk graphite weak sauce... I'm just guessing here. Anyways if the graphite were built up layer by layer would it be better than natural graphite? More precisely would it be "bulk graphene" or would the properties of the graphene vanish on the macro scale? You see, I'm suspicious of the physicists only studying a few atoms and making crazy seeming claims, and after all these years nobody seems to be making a bulk material out of it, except a few people making composites but then the graphene combines its properties with the other materials...

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    $\begingroup$ start here for differences between bulk and thin films spiedigitallibrary.org/conference-proceedings-of-spie/2114/0000/… $\endgroup$ – N. Steinle Mar 31 '19 at 0:29
  • $\begingroup$ Most of the unusual properties of graphene arise from the fact that it is a very thin layer. Single crystals of graphite can be created but they have bulk properties and not thin layer properties. For a bulk material the surface is just a small defect which usually can be neglected. For the graphene the surface is pretty much all it is. $\endgroup$ – nasu Mar 31 '19 at 14:21

Your question is broader than you might have expected. Below you find just an overview on the topic.

Simple answer: Graphene does not exist "as a bulk material". Hence, it cannot behave any differently than it behaves as a single layer. What happens in graphite is an ordered stacking of graphene platelets. Due to the interaction between adjacent layers, the electronic structure of the material changes and all the exceptional single-layer properties get lost. I would start reading here: https://en.wikipedia.org/wiki/Graphite#Structure.

More elaborate answer: When graphene layers are twisted or shifted with respect to each other, even in a bulk, the monolayer signature comes back. "Unordered" stacked layers are called turbostratic graphite. The interaction of the layers is impaired due to misalignment of the honeycomb lattices. Turbostratic graphite has got a distinct Raman spectrum, which is why it is easy to verify. You can find lots of experimental proof, theoretical descriptions and simulations about it. A good read would be Scientific Reports, 6, 19804 (2016) (It's an open access nature report). Again, this should only be a starting point, because tons of work have been published on the topic.

Interestingly, the decoupling of graphene layers in a bulk also works if the layers are separated by more than their usual van-der-Waals distance of 0.335 nm. This holds true if foreign atoms or molecules are intercalated. Intercalation has been widely studied for graphite where the so-called Graphite Intercalation Compounds (GICs) were investigated (see this or this). In a way, this is close to doped graphene in a bulk. The monolayer signature comes back due to the layer separation, and already in 1977 Foley et al. studied an intercalation compound which exhibited the same electrical conductivity as monolayer graphene. At the time though, graphene had not been synthesized and was expected to be thermodynamically unstable. So getting back to your question: People were actually studying bulk materials with single layer graphene properties as early as the seventies...

On an industrial scale, graphene can be cast or filtered or coated to become a free-standing film. This is usually done from the liquid phase. In these films, graphene flakes are randomly oriented and not orderly stacked. They are used as heat spreaders, e.g. in smartphones (Huawei Mate 20X). Some research groups have also presented cables, or macroscopic ribbons. As far as I know, they are not as good as metal wires as of now, but progress seems to be pretty fast. So while there are definitely physicists who are only studying the atomic level, others are preparing macro-materials. And they heavily rely on the knowledge that the physicists gathered earlier.

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