Nanofluid electrolyte advances rechargeable zinc-air batteries

Nanofluid electrolytes for zinc-air batteries: what happened?

Rechargeable zinc-air batteries are aqueous alternatives to lithium-ion: cheaper zinc, water-based chemistry, high theoretical energy density. Two problems slow them: hydrogen evolution and corrosion at the zinc anode, and sluggish oxygen reactions at the air cathode that usually need costly platinum or ruthenium catalysts.

• The nanofluid approach attacks both electrode problems with one low-cost step.
• The team also built earth-abundant bifunctional catalysts for ORR and OER; α-MnO2 with copper doping beat Pt- and Ru-based benchmarks at 2 wt% doping.
• Spent activated carbon from household water filters was turned into MnO2/C nanocomposites; surgical face masks were upcycled into high-surface-area activated carbon.

Why zinc-air?

• High theoretical energy density, low cost, and water-based chemistry compared with lithium-ion systems.
• Relevant for grid storage and electric mobility in India, the release says.

Why does nanofluid electrolytes for zinc-air batteries matter?

• Energy storage: Aqueous zinc-air as a safer storage option.
• S&T: DST-backed materials work with a granted Indian patent.

What can Prelims ask on nanofluid electrolytes for zinc-air batteries?

• Nanofluid electrolyte: silica + ZnO nanoparticles; stable over three months; patent IN570691.
• SASTRA Deemed University, Thanjavur; DST Nano and Advanced Materials Division.
• α-MnO2 with 2 wt% copper doping as bifunctional catalyst.