【Rare Earth Enhanced Electrocatalysis】Fu Gengtao from Nanjing Normal University, Hao Li from Tohoku University, Jong-Min Lee from Nanyang Technological University, Nano Energy: Direct O-O coupling during atomic-level rare earth-activated manganese oxide electrocatalytic oxygen evolution
【Article Information】
Rare earth atoms activate direct O-O coupling during manganese oxide electrocatalytic oxygen evolution
First Author: Li Meng
通讯作者： Jong-Min Lee*，李昊*，付更涛*
Affiliations: Nanjing Normal University, Tohoku University, Nanyang Technological University, Southeast University
【Background】
The efficiency of hydrogen production from water electrolysis is largely limited by the oxygen evolution reaction (OER). Due to the limitation of the linear relationship of oxygen intermediates in the evolution mechanism of OER adsorbates (AEMs), transition metal oxide (TMOs)-based OER catalysts still require a large overpotential (~300 mV) in the basic electrolyte. The relative energy levels of the TM and O-states determine the oxidation order in the OER, and theoretically the formation of *OOH can be avoided by the modulation of the O-band, thus avoiding the limitations of AEM. Studies have shown that rare earth elements (RE) can flexibly adjust the electrocatalytic performance of TM through coupling with valence O2p bands. However, due to the complex bonding environment of rare earth elements, there are few studies on the catalytic promotion mechanism induced by rare earth elements, especially the related systems of RE-TMOs, and the functional definition of rare earth elements is also vague. In addition, there are great differences in the physicochemical properties and crystallization behavior of rare earths and transition metals, and how to couple rare earths and TMOs while ensuring the utilization rate of active sites is still a challenge.
【Introduction】
近日，南京师范大学付更涛教授与日本东北大学大学李昊副教授和南洋理工大学Jong-Min Lee副教授合作，在国际知名期刊Nano Energy上发表题为“Atomic rare earths activate direct O-O coupling in manganese oxide towards electrocatalytic oxygen evolution”的研究文章。 本文章通过Ar等离子体(P)辅助策略构建了在MnO2纳米片上原子分散的RE原子，以局部不对称的[Gd−O−Mn]单元诱导电子在Mn−O处积聚，从而触发表面*OH的逐渐覆盖直接形成(O−O)二聚体，绕过OER的普遍标度关系，实现本征OER活性增强。
Figure 1. Schematic diagram of the direct (O-O) coupling path of the locally asymmetric [Gd−O−Mn] unit activating oxygen evolution reaction.
【Main points of the text】
要点一： 等离子体助力构建[Gd-O-Mn]催化单元
A series of RE monoatoms (P-RE SAs@MnO2, RE=Gd, La, Ce, Tm and Lu) were loaded on MnO2 nanosheets by an Ar plasmon(P)-assisted strategy, and the electronic interactions between RE, Mn and O were studied. Represented by the P-Gd SAs@MnO2, where O as a bridge can ensure that the Gd and Mn atoms are tightly coupled and connected as locally asymmetric [Gd−O−Mn] units. The introduction of Gd−O polarized ionic bonds can induce Gd to contribute electrons to the oxygen sites in the surrounding [Gd−O−Mn] cells, thereby contributing to the construction of special electron-dense oxygen states in the P-Gd SAs@MnO2.
Point 2: Excellent OER catalytic activity
Experimental characterization and theoretical studies have verified that the constructed [Gd−O−Mn] unit promotes excellent OER performance of P-Gd SAs@MnO2. Specifically, P-Gd SAs@MnO2 exhibited low OER overpotential (281 mV@10 mA cm-2), excellent long-range stability, and optimized activation energy (Ea = 32.07 kJ mol−1 at ηj10), outperforming MnO2, commercial RuO2, and most Mn-based catalysts. Similarly enhanced OER performance can be extended to other P-RE SAs@MnO2 (RE = La, Ce, Tm and Lu). In addition, the paper also demonstrated that the construction of the [Gd−O−Mn] site can accelerate the electron accumulation at the end of the MnIV=O intermediate, thereby triggering the contribution of lattice oxygen in the OER process.
Point 3: Clarify the OER enhancement mechanism
Through a combination of experiments and theoretical simulations, this work highlights the origin of rare earth-induced OER performance enhancement and the true active site in the P-Gd SAs@MnO2, which can be attributed to the following aspects: (i) the localized Gd−4f nature of the [Gd−O−Mn] unit site leads to the accumulation of electrons at the O site, which triggers the existence of unstable O2c states in the [Gd−O−Mn] unit site; (ii) the unstable O2c state at the [Gd−O−Mn] unit site tends to be self-stable by dimerization and thus acts as the active site, and tends to assist OER by the direct formation of (O-O) dimer oxygen intermediates; (iii) The formation of (O-O) dimers at the [Gd−O−Mn] site during OER can facilitate modulation in the OER intermediate transition pathway, circumventing the general scaling relationship in the adsorbate evolution mechanism (AEM) by avoiding the formation of *OOH.
【Article Link】
Atomic rare earths activate direct O-O coupling in manganese oxide towards electrocatalytic oxygen evolution
https://doi.org/10.1016/j.nanoen.2024.109868
【About the Corresponding Author】
Prof. Fu Gengtao's Profile:
Fu Gengtao, professor and doctoral supervisor of Nanjing Normal University, national young talent, distinguished professor of Jiangsu Province, and "young and middle-aged leading talent" of Nanjing Normal University. He received his Ph.D. from Nanjing Normal University in 2017, then worked as a postdoctoral researcher at Nanyang Technological University in Singapore and the University of Texas at Austin, and joined the School of Chemical Sciences of Nanjing Normal University in 2021. His research interests include energy electrochemistry, with a particular focus on rare earth-enhanced electrocatalysis. Currently working as the corresponding author/first author at Angew. Chem., Adv. Mater., Energy Environ. He has published 100 papers in journals such as Sci., Adv. Energy Mater., Nano Lett., Chem. Sci., 28 of which have been selected as ESI highly cited papers, with a total citation > 12000, an h-index of 68, and more than 10 authorized invention patents.
He has presided over the general projects of the National Natural Science Foundation of China, the Youth Fund project, the sub-project of the National Key R&D Program, the general project of the Natural Science Foundation of Jiangsu Province, and the scientific and technological innovation project of Nanjing Overseas Students. He has been selected as a Young Changjiang Scholar of the Ministry of Education, a Distinguished Professor of Jiangsu Province, a "Global Highly Cited Researcher" by Clarivate Analytics, and one of the top 2% scientists in the world. He served as a director of Jiangsu Chemistry and Chemical Engineering Society, Adv. Powder Mater., Editorial Board Member of JMMM Journal, Carbon Energy, Mater. Young editorial board member of Today Energy, Chem. Synth., Rare Metal and other journals.
Associate Professor Li Hao's profile:
Hao Li is an associate professor and doctoral supervisor at the Institute for Advanced Study in Materials Science (WPI-AIMR), Tohoku University, Japan, the head of the Digital Catalysis and Battery Laboratory (DigCat & DigBat), and a co-researcher at the Australian Research Council's Centre of Excellence for Green Electrochemical CO2 Conversion (GETCO2). He received his Ph.D. from the Department of Chemistry and the Oden Center for Scientific and Engineering Computing at the University of Texas at Otin, and worked as a postdoctoral fellow in the Department of Physics at the University of Denmark. He is mainly engaged in artificial intelligence materials research, catalysis and material theoretical derivation, theoretical calculation methods and machine learning algorithm development, and new catalyst design. He has received a series of international awards and honors, including the "Young Scholar in Surface Science" (2022 American Chemical Annual Meeting), the "Best Basic Discipline Research of the Year" by the American Institute of Chemical Engineers (AIChE), and the 2021 and 2022 World Highly Cited Scholars. He has been invited to give more than 60 presentations at world-renowned universities and top conferences.
Jong-Min Lee副教授简介:
Jong-Min Lee,新加坡南洋理工大学化学与生物医学工程学院副教授、博士生导师, 博士毕业于哥伦比亚大学化学工程系。 曾在劳伦斯伯克利国家实验室化学科学部和加州大学伯克利分校化学工程系从事博士后研究。 主要研究领域为电化学、绿色化学和纳米技术。 目前以通讯/第一作者在Chem. Soc. Rev., Nat. Energy, Nat. Comm., J. Am. Chem. Soc., Adv. Mater., Joule, Adv. Energy Mater., ACS Nano, ACS Catal.等国际权威学术期刊发表论文200余篇,H-Index 66,入选2023年科睿唯安全球高被引科学家,全球前2%顶尖科学家榜单。 担任Adv. Powder Mater.期刊编委。
【First Author Introduction】
Meng Li is a Ph.D. candidate at Southeast University, and is currently conducting CSC Ph.D. joint training at Nanyang Technological University, Singapore. He graduated from Nanjing Normal University with a master's degree in 2018. His main research interests are the application of rare earth-based single-atom catalysts in the field of energy and catalysis. To date, the first author and co-first author have published a number of studies in Adv. Mater., Angew. He has published more than 10 papers in journals such as Chem. Int. Ed., Adv. Energy Mater., Nano Energy, Small, etc.