Breathing-Mimicking Electrocatalysis for Oxygen Evolution and Reduction

By Jun Li, Yangying Zhu, Wei Chen, Zhiyi Lu, Jinwei Xu, Allen Pei, Yucan Peng, Xue-li Zheng, Zewen Zhang, S. Chu and 1 more. Joule, 2019

182 citations recorded by the source corpus.

Summary Electrocatalytic oxygen evolution and reduction reactions play a central role in clean energy technologies. Despite recent efforts to achieve fast gas reactant delivery to the reaction interface, efficient gas product evolution from the catalyst/electrolyte interface remains challenging. Inspired by the mammalian breathing process, here we developed an efficient electrocatalytic system to enable ample gas-solid-liquid three-phase contact lines and bidirectional gas pathways for evolution and consumption. During the oxygen evolution reaction, the newly formed O2 molecules quickly diffuse to the gas phase, waiving the bubble formation energy in the electrolyte. A record low overpotential of 190 mV at 10 mA⋅cm−2 was achieved using Au/NiFeOx catalysts. During the oxygen reduction reaction, O2 gas can transport to the catalyst/electrolyte interface, overcoming low O2 solubility in water and leading to ∼25-fold higher current densities for Ag/Pt bilayer nanoparticle catalysts. This breathing-mimicking design demonstrates efficient three-phase catalysis with a minimal catalyst thickness.

Subfields: Electrical and Electronic Engineering, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/b040780a51218f5d86fa667a0873cf77ab4d1626