Hybrid Gold Catalyst Solves Stability Issues in Zinc-Air Batteries

Single-atom catalysts hold immense potential for energy storage, yet they are famously unstable; isolated atoms often aggregate due to high surface energy, diminishing their effectiveness. A research team has now addressed this activity-stability trade-off by engineering a hybrid gold catalyst, termed Au ACSA-ZrO₂.

Using a mild thermal anchoring strategy at 200 °C, the scientists stabilised dispersed gold single atoms alongside clusters on a zirconium dioxide support. This process induces strong metal-support interactions, forming covalent Au–O–Zr bonds. These bonds act as firm anchors, inhibiting the migration and coalescence of atoms while facilitating interfacial charge transfer. Furthermore, electronic coupling between the gold atoms and adjacent clusters modifies orbital hybridisation, optimising how oxygen intermediates adhere during reactions.

The impact on performance is significant. When integrated into a zinc-air battery, this dual-site catalyst accelerated oxygen reduction and evolution kinetics, delivering a round-trip efficiency of 71.07%. Crucially, the battery showed negligible decay over 260 hours of continuous cycling, proving that precise orbital control can lead to exceptionally durable energy devices.