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Title: Discovery of LaAlO3 as an efficient catalyst for two-electron water electrolysis towards hydrogen peroxide

Electrochemical two-electron water oxidation reaction (2e-WOR) has drawn significant attention as a promising process to achieve the continuous on-site production of hydrogen peroxide (H2O2). However, compared to the cathodic H2O2generation, the anodic 2e-WOR is more challenging to establish catalysts due to the severe oxidizing environment. In this study, we combine density functional theory (DFT) calculations with experiments to discover a stable and efficient perovskite catalyst for the anodic 2e-WOR. Our theoretical screening efforts identify LaAlO3perovskite as a stable, active, and selective candidate for catalyzing 2e-WOR. Our experimental results verify that LaAlO3achieves an overpotential of 510 mV at 10 mA cm−2in 4 M K2CO3/KHCO3, lower than those of many reported metal oxide catalysts. In addition, LaAlO3maintains a stable H2O2Faradaic efficiency with only a 3% decrease after 3 h at 2.7 V vs. RHE. This computation-experiment synergistic approach introduces another effective direction to discover promising catalysts for the harsh anodic 2e-WOR towards H2O2.

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Nature Publishing Group
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Journal Name:
Nature Communications
Medium: X
Sponsoring Org:
National Science Foundation
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