A High-Entropy Oxide as High-Activity Electrocatalyst for Water Oxidation
Citations Over TimeTop 10% of 2023 papers
Abstract
High-entropy materials are an emerging pathway in the development of high-activity (electro)catalysts because of the inherent tunability and coexistence of multiple potential active sites, which may lead to earth-abundant catalyst materials for energy-efficient electrochemical energy storage. In this report, we identify how the multication composition in high-entropy perovskite oxides (HEO) contributes to high catalytic activity for the oxygen evolution reaction (OER), i.e., the key kinetically limiting half-reaction in several electrochemical energy conversion technologies, including green hydrogen generation. We compare the activity of the (001) facet of LaCr0.2Mn0.2Fe0.2Co0.2Ni0.2O3-δ with the parent compounds (single B-site in the ABO3 perovskite). While the single B-site perovskites roughly follow the expected volcano-type activity trends, the HEO clearly outperforms all of its parent compounds with 17 to 680 times higher currents at a fixed overpotential. As all samples were grown as an epitaxial layer, our results indicate an intrinsic composition-function relationship, avoiding the effects of complex geometries or unknown surface composition. In-depth X-ray photoemission studies reveal a synergistic effect of simultaneous oxidation and reduction of different transition metal cations during the adsorption of reaction intermediates. The surprisingly high OER activity demonstrates that HEOs are a highly attractive, earth-abundant material class for high-activity OER electrocatalysts, possibly allowing the activity to be fine-tuned beyond the scaling limits of mono- or bimetallic oxides.
Related Papers
- → Thermo-selenizing to rationally tune surface composition and evolve structure of stainless steel to electrocatalytically boost oxygen evolution reaction(2020)59 cited
- → Facile synthesis of interlaced flower-like layered double hydroxides grown on porous CoMoP as a highly efficient electrocatalyst for hydrogen evolution reaction(2023)33 cited
- → Oxygen Evolution Reaction (OER) on Clean and Oxygen Deficient Low-Index SrTiO3 Surfaces: A Theoretical Systematic Study(2019)20 cited
- → Self-supported Ni2P nanoarrays as efficient electrocatalysts for oxygen evolution reaction and hydrogen evolution reaction(2023)5 cited
- → Cover Picture: A 3D Nanoporous Ni–Mo Electrocatalyst with Negligible Overpotential for Alkaline Hydrogen Evolution (ChemElectroChem 7/2014)(2014)4 cited