First Metal-Free Catalyst for Rechargeable Zinc-Air Batteries

Hey is this another graphene use in the pipeline?

..."Zinc-air batteries mix oxygen from the air with zinc in a liquid alkaline electrolyte to create a charge. The batteries can have three times the energy density of lithium-ion batteries, but have been sluggish. To counter that problem, researchers are seeking different catalyst materials. This catalyst is a stable carbon aerogel, or foam, with pores ranging from 2 to 50 nanometers in diameter, providing enormous surface area and room for the battery electrolyte to diffuse.

The researchers followed a foam-making procedure published by Stanford University scientists in 2012. They polymerized molecules of the organic compound aniline into long chains in a phytic acid solution, then freeze-dried the three-dimensional hydrogel into an aerogel. "What we did that's new is carbonized the 3-D structure, changing it into a graphitic carbon material," Zhang said. To do that, the researchers heated the aerogel to 1,000 degrees Celsius in the absence of oxygen.

The process, called pyrolysis, caused a thermochemical reaction, turning the foam into a graphitic network, with many graphene edges that proved to be crucial to catalysis. "This is a low-cost, one-step, scalable process," Dai said. "The electrocatalyst produces comparable or better results than more costly materials." The aniline infuses, or dopes, the foam with nitrogen, which enhances the oxygen reduction reaction. Phytic acid infuses the foam with phosphorus. "The co-doping of nitrogen and phosphorus enhances both the oxygen reduction and oxygen evolution reactions, as confirmed by the first-principles calculations", Xia said."...

Read more at:

http://www.energyharvestingjournal.com/articles/7673/first-metal-free-catalyst-for-rechargeable-zinc-air-batteries

Bonus link...
http://www.aerogel.org/?p=71