Scientists and researchers are still coming up with ways to use graphene, perhaps the greatest wünder-material in recent memory.
Graphene, an atom-thick single-layer two-dimensional lattice of pure carbon, has been known for decades, yet only recently has been getting the attention it deserves. So far, research into graphene has yielded, at least, prototype technologies in water purification, semiconductors, photovoltaic solar power, lithium-ion batteries, supercapacitors. Is there anything that graphene can’t do? Scientists are still discovering graphene’s unique properties.
Recently, researchers discovered that a single droplet of salt water running across graphene generated an electric charge, just a single droplet, which may be why this has taken so long to discover. Sitting still, the charge around the droplet is equal, but if the droplet moves, electrons are absorbed and desorbed by the graphene, generating an electric charge. At best, the voltage reaches maximum potential of 30 mV, pretty small compared to, say, 1,500 mV of the typical “AA”-size battery. It’s a small charge, but the Chinese scientists are confident it can be scaled up dramatically.
Interestingly, flowing saltwater won’t generate a charge on graphene, as the phenomenon seems to depend on the difference in charge between the leading and trailing edges of the saltwater droplet. Large-scale saltwater graphene generators may be a long way off, but these results are encouraging, making use of the most-abundant substance on the planet to generate carbon-free electricity could be a huge leap forward in addressing climate change. Considering the need for freshwater in many coastal areas, I wonder if at least a saltwater graphene self-powered graphene desalination plant would be feasible.
Photo credit: DocJ96 / Foter / Creative Commons Attribution-NonCommercial 2.0 Generic (CC BY-NC 2.0)