Recent articles [1, 2, 3, 4] show that people are interested in producing graphene in many differ ways. The referenced articles provide descriptions of various means of manufacturing graphene. Reference 1 covers a few of the methods. Slide 10 in reference 3 lists a number of suppliers with their manufacturing process listed. There are a large number of other articles available on the manufacturing methods.
There is concern that there could be a safety issue in that a sheet of graphene can enter cells. Reference 5 mentions that a thickness of less than 4 nm provides the ability to enter into cells. Reference 6 states: “They found that the jagged edges of graphene nanoparticles, super sharp and super strong, easily pierced through cell membranes in human lung, skin and immune cells, suggesting the potential to do serious damage in humans and other animals.” Let’s consider this issue. First produced graphene has a small area and is normally attached to a carrier. That gives it thickness that reduces or eliminates the possibility of being a cutting edge. To be a source of danger, the graphene sample would need to be much larger than currently manufacturable. If it were larger in area, does it retain its stiffness? Or does it tend to bend? If it bends, does that reduce or eliminate the probability of being able to do damage?
To examine this from a different viewpoint, consider hydrogen. As an element, it is the lightest. Consequently, some of the early “lighter-than-air” devices were constructed with hydrogen as the lifting mechanism. The unfortunate consequences of hydrogen’s reactivity with a proper stimulus is evidenced by the destruction of the von Hindenburg zeppelin. In today’s environment of protect first on the real or imagined potential harm, work on using hydrogen would be strongly opposed. This would have eliminated the possibility of hydrogen fueled vehicles. The energy comes from the combination of hydrogen and oxygen, which yields power and water. Knowing the reactivity of hydrogen, there are means of reducing the dangers of hydrogen as used in vehicles. What will the application of graphene or carbon nanotubes yield that will provide benefit for humanity?
Reference 7 states: “All interesting nanomaterials have peculiar properties, and being declared hazardous does not doom a material, since many hazardous materials are already successfully used in semiconductor manufacturing, including lead, mercury, and cadmium.” We must remember this in the development of any nanomaterial product and provide sufficient safety precautions.
With the strong emphasis on graphene, it raises the question: “Is this emphasis on graphene diverting attention on other similar materials?” Graphene is a hot research topic, but there are other two-dimensional materials. (Any three dimensional material that is only one atom thick is normally qualified as having no thickness or being two-dimensional. Among these materials are Boron Nitride, MoS2, Bi2Te3, Bi2Se3, with new ones being added regularly.)
There is another question that needs to be asked. Assume that some of these developments are actually producible. What are we going to do with them? How will they make life better?
References:
[3] http://web.ornl.gov/adm/partnerships/events/Dec_Spark/Speight_Graphene%20v5.pdf
[4] http://gigaom.com/2014/05/23/graphene-production-could-scale-up-with-this-new-technique-out-of-mit/
[5] http://www.pnas.org/content/early/2013/07/09/1222276110.full.pdf
[6] http://www.gizmag.com/graphene-bad-for-environment-toxic-for-humans/31851/