气候变化领域集成服务门户(CCPortal): Activation of ultrathin SrTiO3 with subsurface SrRuO3 for the oxygen evolution reaction

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DOI	10.1039/c8ee00210j
	Activation of ultrathin SrTiO3 with subsurface SrRuO3 for the oxygen evolution reaction
	Akbashev A.R.; Zhang L.; Mefford J.T.; Park J.; Butz B.; Luftman H.; Chueh W.C.; Vojvodic A.
发表日期	2018
ISSN	17545692
起始页码	1762
结束页码	1769
卷号	11 期号:7
英文摘要	Water electrolysis occurs via the oxygen/hydrogen evolution reactions. Achieving sufficiently high oxygen evolution reaction (OER) activity while maintaining stability of the active catalyst surface is a primary challenge of designing OER catalysts. Often high electrocatalytic activity is accompanied by structural instability. This is the case for the metallic perovskite oxide SrRuO3 (SRO), which exhibits rapid dissolution under OER conditions, both as thin-films and as nanoparticles. On the other hand, large band-gap perovskite oxides such as SrTiO3 (STO) are inactive for OER in the dark but are stable. In this work, we demonstrate that burying as little as one unit cell of SRO beneath an ultrathin STO capping layer activates the otherwise inert electrocatalyst and gives excellent stability. Using density functional theory (DFT) calculations, we find that such a chemical modification of STO by sub-surface SRO introduces new 4d electronic states including Ru states within the STO band gap, raising the energy level of the electrons, changing the electronic hybridization, and facilitating an easy transfer to the adsorbed intermediates. We validate this hypothesis experimentally using atomically precise heteroepitaxial deposition. We find that a single-unit-cell layer of SRO is sufficient to activate the topmost STO layer towards OER; burying SRO underneath two unit cells of STO protects the inherently unstable SRO against corrosion during OER. Generally, our layered heterostructures are model systems of oxide core-shell structures, where an unstable catalyst (core) is protected against degradation and electronically activates the otherwise inactive shell. As demonstrated in this work, the growth of ultrathin heterostructures establishes a rigorous platform for screening core/shell nanoparticle combinations/thicknesses, and elucidates sub-surface activation mechanism for achieving stable and active oxide electrocatalysts. © 2018 The Royal Society of Chemistry.
英文关键词	Chemical activation; Chemical modification; Corrosion protection; Density functional theory; Electrocatalysts; Energy gap; Heterojunctions; Nanoparticles; Oxide films; Oxygen; Perovskite; Perovskite solar cells; Strontium titanates; Adsorbed intermediates; Core shell structure; Core/shell nanoparticles; Electrocatalytic activity; Electronic hybridization; Heteroepitaxial deposition; Oxygen evolution reaction; Structural instability; Ruthenium compounds; catalysis; catalyst; chemical reaction; electrokinesis; electron; inorganic compound; nanoparticle
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/190191
作者单位	Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, United States; Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, United States; Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104, United States; Institut für Werkstofftechnik and Gerätezentrum für Mikro- und Nanoanalytik (MNaF), Universität Siegen, Siegen, 57068, Germany; Surface Characterization Facility, Lehigh University, Bethlehem, PA 18105, United States
推荐引用方式 GB/T 7714	Akbashev A.R.,Zhang L.,Mefford J.T.,et al. Activation of ultrathin SrTiO3 with subsurface SrRuO3 for the oxygen evolution reaction[J],2018,11(7).
APA	Akbashev A.R..,Zhang L..,Mefford J.T..,Park J..,Butz B..,...&Vojvodic A..(2018).Activation of ultrathin SrTiO3 with subsurface SrRuO3 for the oxygen evolution reaction.Energy & Environmental Science,11(7).
MLA	Akbashev A.R.,et al."Activation of ultrathin SrTiO3 with subsurface SrRuO3 for the oxygen evolution reaction".Energy & Environmental Science 11.7(2018).