Formation of H 2 O 2 in Near‐Neutral Zn‐air Batteries Enables Efficient Oxygen Evolution Reaction
Year: 2024
Type: article
Abstract: Rechargeable Zn‐air batteries (ZABs) with near‐neutral electrolytes hold promise as cheap, safe and sustainable devices, but they suffer from slow charge kinetics and remain poorly studied. Here we reveal a charge storage mechanism of near‐neutral Zn‐air batteries that is mediated by formation of dissolved hydrogen peroxide upon cell discharge and its oxidation upon charge. This H 2 O 2 ‐mediated pathway facilitates oxygen evolution reaction (OER) at ~1.5 V vs. Zn 2+ /Zn, reducing charge overpotentials by ~0.2–0.5 V and mitigating carbon corrosion—a common issue in ZABs. The manifestation of this mechanism strongly depends on the electrolyte composition and positive electrode material, contributing up to ~60 % of the capacity with ZnSO 4 solutions and carbon nanotubes. Enhancing the H 2 O 2 ‐mediated pathway offers a route to higher energy efficiency and durability in near‐neutral ZABs, advancing practical, sustainable energy storage.
Institutions: Bar-Ilan University, Ben-Gurion University of the Negev
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,510
OpenAlex ID: W4405000839