A new operando surface restructuring pathway via ion-pairing of catalyst and electrolyte for water oxidation

A new operando surface restructuring pathway via ion-pairing of catalyst and electrolyte for water oxidation

Zhuang, Linzhou (East China University of Science and Technology; University of Queensland)
Li, Zhiheng (University of Queensland)
Li, Mengran (TU Delft ChemE/Materials for Energy Conversion and Storage; University of Queensland)
Tao, Haolan (East China University of Science and Technology)
Mao, Xin (Queensland University of Technology)
Lian, Cheng (East China University of Science and Technology)
Ge, Lei (University of Southern Queensland)
Du, Aijun (Queensland University of Technology)
Xu, Zhi (East China University of Science and Technology)

2023

The highly efficient and stable electrolysis needs the rational control of the catalytically active interface during the reactions. Here we report a new operando surface restructuring pathway activated by pairing catalyst and electrolyte ions. Using SrCoO_3-δ-based perovskites as model catalysts, we unveil the critical role of matching the catalyst properties with the electrolyte conditions in modulating catalyst ion leaching and steering surface restructuring processes toward efficient oxygen evolution reaction catalysis in both pH-neutral and alkaline electrolytes. Our results regarding multiple perovskites show that the catalyst ion leaching is controlled by catalyst ion solubility and anions of the electrolyte. Only when the electrolyte cations are smaller than catalyst's leaching cations, the formation of an outer amorphous shell can be triggered via backfilling electrolyte cations into the cationic vacancy at the catalyst surface under electrochemical polarization. Consequently, the current density of reconstructed SrCoO_3-δ is increased by 21 folds compared to the pristine SrCoO_3-δ at 1.75 V vs reversible hydrogen electrode and outperforms the benchmark IrO₂ by 2.1 folds and most state-of-the-art electrocatalysts in the pH-neutral electrolyte. Our work could be a starting point to rationally control the electrocatalyst surface restructuring via matching the compositional chemistry of the catalyst with the electrolyte properties.

Cation size-matching
Non-acidic medium
Operando surface restructuring
Oxygen evolution
Strontium ion leaching

http://resolver.tudelft.nl/uuid:2368d80a-c1c3-4848-a4fd-7c5cacc61d2c

https://doi.org/10.1016/j.cej.2022.140071

1385-8947

Chemical Engineering Journal, 454

Institutional Repository

journal article

© 2023 Linzhou Zhuang, Zhiheng Li, Mengran Li, Haolan Tao, Xin Mao, Cheng Lian, Lei Ge, Aijun Du, Zhi Xu, More Authors