Pd nanoparticles on ZnO-passivated porous carbon by atomic layer deposition: an effective electrochemical catalyst for Li-O₂ battery

Abstract

Uniformly dispersed Pd nanoparticles on ZnO-passivated porous carbon were synthesized via an atomic layer deposition (ALD) technique, which was tested as a cathode material in a rechargeable Li-O2 battery, showing a highly active catalytic effect toward the electrochemical reactions-in particular, the oxygen evolution reaction. Transmission electron microscopy (TEM) showed discrete crystalline nanoparticles decorating the surface of the ZnO-passivated porous carbon support in which the size could be controlled in the range of 3-6 nm, depending on the number of Pd ALD cycles performed. X-ray absorption spectroscopy (XAS) at the Pd K-edge revealed that the carbon-supported Pd existed in a mixed phase of metallic palladium and palladium oxide. The ZnO-passivated layer effectively blocks the defect sites on the carbon surface, minimizing the electrolyte decomposition. Our results suggest that ALD is a promising technique for tailoring the surface composition and structure of nanoporous supports for Li-O2 batteries.

Electrolyte Stability and Discharge Products of an Ionic-Liquid-Based Li–O2 Battery Revealed by Soft X-Ray Emission Spectroscopy

“…The spectrum of the cathode at potential V 2 is very similar to the one of the electrolyte, as displayed in Figure S2, suggesting the formation of very small amounts of O-containing discharge products. 12 To quantify the different oxygen contributions, the spectrum is fitted with three components, as described in the following. First, we performed a three-component fit, using the spectra of Electrolyte, GDL, and lithium peroxide.…”

High‐Energy‐Density Metal–Oxygen Batteries: Lithium–Oxygen Batteries vs Sodium–Oxygen Batteries

“…[53,[101][102][103][104][105][106][107][108][109][110][111][112][113] However, these results have shown that it is impossible to maximize the electrochemical performance of a Li-O 2 battery without distinguishing the role of each catalyst for the ORR or OER. [53,[101][102][103][104][105][106][107][108][109][110][111][112][113] However, these results have shown that it is impossible to maximize the electrochemical performance of a Li-O 2 battery without distinguishing the role of each catalyst for the ORR or OER.…”

Atomic Layer Deposition for Lithium‐Based Batteries

“…The same group also tested ZnO instead of Al 2 O 3 as the passivation layer. The Pd grew faster on the ZnO layer, the overpotential on charge was almost zero, and the cyclability was also improved . The passivated cathode is well suited to study the catalytic mechanisms, and the metal oxide layer can improve the adhesion of catalysts on non‐carbon cathodes …”