Baek Jihyun, Jin Qiu, Johnson Nathan Scott, Jiang Yue, Ning Rui, Mehta Apurva, Siahrostami Samira, Zheng Xiaolin
Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305, USA.
Department of Chemistry, University of Calgary, Calgary, AB, T2N 1N4, Canada.
Nat Commun. 2022 Nov 25;13(1):7256. doi: 10.1038/s41467-022-34884-4.
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 (HO). However, compared to the cathodic HO generation, 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 LaAlO perovskite as a stable, active, and selective candidate for catalyzing 2e-WOR. Our experimental results verify that LaAlO achieves an overpotential of 510 mV at 10 mA cm in 4 M KCO/KHCO, lower than those of many reported metal oxide catalysts. In addition, LaAlO maintains a stable HO Faradaic 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 HO.
电化学双电子水氧化反应（2e-WOR）作为一种实现过氧化氢（HO）连续现场生产的有前景的过程，已引起了广泛关注。然而，与阴极生成HO相比，由于阳极环境的强氧化性，阳极2e-WOR的催化剂开发更具挑战性。在本研究中，我们将密度泛函理论（DFT）计算与实验相结合，以发现一种用于阳极2e-WOR的稳定且高效的钙钛矿催化剂。我们的理论筛选工作确定LaAlO钙钛矿是催化2e-WOR的稳定、活性和选择性候选物。我们的实验结果证实，LaAlO在4M KCO/KHCO中，在10mA cm时过电位为510mV，低于许多已报道的金属氧化物催化剂。此外，相对于可逆氢电极（RHE），在2.7V下3小时后，LaAlO保持稳定的HO法拉第效率，仅下降3%。这种计算-实验协同方法为发现用于苛刻的阳极2e-WOR以生成HO的有前景的催化剂引入了另一个有效方向。
