Real-Time Imaging of the Electrochemical Process in Na-O<sub>2</sub> Nanobatteries Using Pt@CNT and Pt<sub>0.8</sub>Ir<sub>0.2</sub>@CNT Air Cathodes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31825592.
- Also identified by DOI 10.1021/acsnano.9b07961.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Compared to lithium-oxygen batteries, sodium-oxygen (Na-O<sub>2</sub>) batteries exhibit a number of advantages: extremely low cost, low charging overpotential, and stability under nitrogen. However, accumulation of insoluble discharge products and failure of catalysts often result in poor performance of Na-O<sub>2</sub> batteries and limit their cycling life. In this work, electrochemical reactions of Na-O<sub>2</sub> batteries were directly investigated <i>in situ</i> by assembling a solid-state Na-O<sub>2</sub> nanobattery in an aberration-corrected environmental transmission electron microscope. During discharge, NaO<sub>2</sub> hollow spheres formed and expanded continuously, accompanying their partial decomposition into Na<sub>2</sub>O<sub>2</sub>. These spheres shrank and collapsed into Na<sub>2</sub>O<sub>2</sub> nanoparticles during the charging process. Carbon nanotubes doped with Pt and bimetallic Pt/Ir nanoscale catalyst can promote product formation and reversible evolution. In-depth investigation of the electrochemical reaction mechanism in Na-O<sub>2</sub> cells helps to accelerate the development of metal-air devices.