Researchers at TU Darmstadt have developed a catalyst for rechargeable zinc-air batteries that survived 500 charge and discharge cycles in testing. The material is a composite of nanoscale nickel-iron spinel particles attached to carbon nanohorns, with nitrogen and phosphorus added to the carbon surface. It is described in Advanced Science. Zinc-air batteries can theoretically store up to five times more energy than lithium-ion, but poor rechargeability has kept them out of most markets. This work targets that blocker by keeping the triple junction, where catalyst, electrolyte, and oxygen meet, stable during operation. The chemistry uses widely available iron, nickel, and carbon rather than lithium, which matters for supply chains.
