Published as part of Chemical Reviews virtual special issue “Operando and In Situ Studies in Catalysis and Electrocatalysis”. Like people, “the catalyst is itself and its circumstance”, paraphrasing the statement of Spanish social philosopher Ortega y Gasset, who believed that individuals are inseparable from their surroundings. Just as understanding people requires considering their social, labor, family, and religious context, a comprehensive grasp of catalysis necessitates studying it in its real operational conditions. While in situ characterization offers insights into a material under controlled conditions approximating working environments, it falls short of capturing the holistic nature of catalysis, where all contributing factors and performances are interconnected and relevant. Analyzing a material’s performance without concurrently understanding its structure during operation is as limited as characterizing a catalyst’s activity without insight into its structure at work. The operando methodology bridges this gap by concomitantly integrating the characterization of a catalyst structure while it is functioning with the analysis of its performance. Unlike in situ studies, the operando approach involves a catalytic reactor─more than just a cell for acquiring spectra or microscopy images─where the catalyst is characterized while actively working (hence “operando” in Latin). Consequently, the operando methodology provides concurrent and pertinent data on both the structure/composition and activity from the actual catalytic act. The experimental maturity in physical chemistry sciences underscores a fundamental truth: catalysis cannot be comprehended without a synergistic combination of spectroscopy, diffraction and microscopy, i.e., without a deep understanding of the catalyst’s morphology, structure, and surface/bulk composition and their intricate interplay with reacting molecules and reaction conditions. Studying catalysts under reactive conditions has long been fundamental in catalysis. Over time, the number of studies characterizing catalysts has grown exponentially, serving as a crucial tool for scientists seeking to deepen their understanding of catalytic processes. Words create realities: introducing the term “operando” about 20 years ago marked a significant conceptual milestone. Since then, the scientific community has embraced this approach, leading to the development of new spectroscopic methods. These advancements have significantly expanded the scope of operando techniques, making them applicable to various functional materials. Today, characterization studies are integral components of most publications on heterogeneous catalysts. A literature review reveals that approximately half of the papers on heterogeneous catalysis employ in situ methodologies, with one-fifth utilizing operando techniques. Scientists over the years have realized that performance catalysts are highly complex dynamic entities, and as such, their understanding requires major experimental as well as theoretical method development efforts, digressing from the traditional static conception of the catalytically active site, considering the possibility of multiple active motifs which also evolve during reaction, while bridging the materials and environmental gaps. In the words of Albert Einstein, “everything should be made as simple as possible, but not simpler.” Such oversimplification, at times also mandated by the nature and operation limitations of the surface science characterization methods commonly used within our catalysis community, has been a hurdle which has impaired the progress of the field for decades. Fortunately, the mindset of researchers in this field has drastically changed in the last decades, as the present review issue illustrates. In this virtual thematic issue, we provide a comprehensive overview of recent advancements in in situ and operando studies in thermal catalysis and electrocatalysis. Additionally, we offer insights into future developments in this field. Catalysts are inherently dynamic materials, capable of undergoing transformations in response to various environmental factors or stimuli such as temperature, pressure, electrical potential, gas and/or liquid composition, and reaction time. These fluctuations profoundly influence the interactions between the catalyst and the gas and liquid phase, thereby influencing the surface and bulk structure and properties of the catalytic material. It is thus paramount to grasp this intricate interplay to facilitate a knowledge-driven exploration of novel catalytic materials, pinpointing structural features directly pertinent to catalytic activity while pushing the boundaries of time and spatial resolutions. (1−3) Structural phenomena play a crucial role in catalyst performance. They determine the electronic local properties of active sites, control their dynamic appearance and regeneration, and on larger length scales affect the transport properties of molecules and energy. Molecular spectroscopy, like infrared spectroscopy, offers valuable insights into changes induced by reacting molecules and environmental conditions. (4) On the other hand, neutron scattering, while less commonly utilized, provides exceptionally precise structural information for light elements, effectively complementing X-ray and photon-based techniques. (5) Solid–liquid interphase reactions have gained increasing importance, especially in electrocatalysis. Techniques such as liquid cell transmission electron microscopy, (2) scanning electrochemical probe microscopy, (6) X-ray scattering, (7) and X-ray computed tomography (8) offer critical insights into both external and internal surfaces, facilitating the quantification of electrode texture, morphology, and tortuosity. These assessments connect the scales in space at times that only collectively can describe the mode of operation of a catalytic process. The operando results are essential for understanding catalyst evolution and dynamics and its deactivation/fouling during operation. Given the complex nature of species at the solid–liquid interface, highly sensitive and selective techniques like sum-frequency generation are indispensable for reporting their molecular information. (9) Similarly, understanding photocatalytic phenomena is an increasingly important challenge. (3) Nonetheless, and despite tremendous recent progress, it should be realized that true operando characterization is not always possible with currently available combinations of reactors and spectrometers. Moreover, significant additional work must be dedicated to overcome current temporal resolution barriers as well as those related to multiple length-scale catalyst characterization or simultaneous spectro-microscopy analysis to achieve spatially resolved information on the catalyst’s morphology, structure, and composition. Here the application of Artificial Intelligence for real-time data analysis and deep automation may bring a breakthrough in collecting information in statistically relevant quantities and wider ranges of experimental conditions that are strictly limited today through the practices of resource allocation. There is always the need to disentangle spectator from active species within the myriad of experimental data acquired, which mandates close interactions of experimental and theoretical groups. A prerequisite to such cooperative effort is the acquisition of kinetically resolved data through steady-state isotopic transient kinetic analysis (SSITKA) or other periodic perturbation techniques, like modulation-excitation spectroscopy (MES). These experiments can only be executed in veritable reactors characterized for their gas dynamical behavior under the pressure conditions applied in the experiment. Here a deficit appears in the current operando approach indicated by the scarce presentation of kinetic data besides conversion values which are of limited value when they are not related to the experimental conditions. Future evolution of the operando methodology may put more weight on evaluating the kinetic information with comparable scrutiny as the spectroscopic or imaging information. Whereas in electrocatalytic experiments the presence of the liquid electrolyte fixes the pressure (chemical potential) to realistic conditions, this is not as often the case for thermocatalytic experiments. Here, either experiments at realistic pressures are of limited surface sensitivity or surface-sensitive experiments are very demanding at performance pressures. The application of model nanostructured systems is a frequent way-out, but it requires careful justification if the behavior of a related performance (industrially relevant) system is to be analyzed. Kinetic parameters obtained under operando conditions would be evidence for having bridged the experimental gaps all the way in both pressure and material’s complexity when extrapolating the operando results to “real” reactor operation. After all, measuring the steady-state kinetics of a catalytic system consisting of catalyst, reactants, and reactor is still the most sensitive “spectrometer” for catalytic studies. To conclude, Max Planck wisely stated that “application must be preceded by recognition”. The present issue beautifully illustrates the breath of experimental tools that we have now available to “recognize”, i.e. to gain in depth insight into, the complexity of catalytic materials while at work. Only when at least part of such complexity has been unveiled can one entertain the thought of transferring such knowledge into much needed applications for a sustainable society. Beatriz Roldán Cuenya is currently the Director of the Department of Interface Science at the Fritz-Haber Institute of the Max-Planck Society in Berlin (Germany). She is an Honorary Professor at the Technical University Berlin, at the Free University Berlin, and at the Ruhr-University Bochum, all in Germany. Also, she serves as a Distinguished Research Professor at the University of Central Florida (USA). She completed her M.S./B.S. in Physics at the University of Oviedo (Spain) in 1998, followed by a Ph.D. in Physics from the University of Duisburg-Essen (Germany) in 2001. She carried out her postdoctoral research in Chemical Engineering at the University of California Santa Barbara (USA) from 2001–2003. In 2004, she joined the Department of Physics at the University of Central Florida as Assistant Professor, where she became a Full Professor in 2012. In 2013 Prof. Roldán Cuenya moved back to Germany as Chair Professor of Solid State Physics at the Ruhr-University Bochum, where she stayed until she joined the FHI in 2017. Prof. Roldán Cuenya’s research program explores physical and chemical properties of nanostructures, with emphasis on advancements in thermal and electro-catalysis based on operando microscopic and spectroscopic characterization. Miguel A. Bañares holds the position of Full Research Professor at the Institute for Catalysis and Petroleum Chemistry, CSIC, located in Madrid, Spain. Previously, he served as the deputy vice president at CSIC, the Spanish National Research Council. The research conducted by the Bañares group focuses on elucidating structure–performance relationships in catalysis. They achieve this by integrating spectroscopy with simultaneous activity measurement during catalytic reactions, a methodology known as operando, a term he coined in 2002. In recognition of his seminal operando methodology work, Bañares was awarded an honorary doctorate degree, Doctor Honoris Causa, by the Université de Caen Normandie in France. He earned his Bachelor of Science and Ph.D. degrees from the Universidad de Salamanca in Spain. This article references 9 other publications. This article has not yet been cited by other publications. This article references 9 other publications.

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简介：催化和电催化的操作和原位研究


作为《化学评论》虚拟特刊“催化和电催化的操作和原位研究”的一部分发表。就像人一样，“催化剂是其自身及其环境”，这是西班牙社会哲学家奥尔特加·伊·加塞特（Ortega y Gasset）的说法，他认为个人与周围环境密不可分。正如了解人需要考虑他们的社会、劳动、家庭和宗教背景一样，全面掌握催化作用也需要在其实际运作条件下进行研究。虽然原位表征可以在接近工作环境的受控条件下深入了解材料，但它无法捕捉催化的整体性质，其中所有影响因素和性能都是相互关联和相关的。分析材料的性能而不同时了解其在操作过程中的结构与表征催化剂的活性而不了解其工作结构一样受到限制。操作方法通过同时整合催化剂结构的表征和性能分析来弥补这一差距。与原位研究不同，操作方法涉及催化反应器（不仅仅是用于获取光谱或显微镜图像的单元），其中催化剂在积极工作的同时进行表征（因此拉丁语中的“操作”）。因此，操作方法提供了有关实际催化作用的结构/组成和活性的并发且相关的数据。 物理化学科学的实验成熟强调了一个基本事实：如果没有光谱学、衍射和显微镜的协同组合，即没有对催化剂的形态、结构和表面/本体组成及其与催化剂的复杂相互作用的深入了解，就无法理解催化作用。反应分子和反应条件。长期以来，研究反应条件下的催化剂一直是催化领域的基础。随着时间的推移，表征催化剂的研究数量呈指数级增长，成为科学家加深对催化过程理解的重要工具。言语创造现实：大约 20 年前引入“ operando ”一词标志着一个重要的概念里程碑。从那时起，科学界就接受了这种方法，从而导致了新的光谱方法的发展。这些进步显着扩大了操作技术的范围，使其适用于各种功能材料。如今，表征研究已成为大多数多相催化剂出版物的重要组成部分。文献综述显示，大约一半的多相催化论文采用原位方法，其中五分之一采用操作技术。 多年来，科学家们已经意识到性能催化剂是高度复杂的动态实体，因此，对它们的理解需要大量的实验和理论方法开发工作，偏离催化活性位点的传统静态概念，考虑到多个活性位点的可能性图案也在反应过程中演变，同时弥合了材料和环境的差距。用阿尔伯特·爱因斯坦的话来说，“一切都应该尽可能简单，但不能过于简单。这种过度简化，有时也是由于我们催化界常用的表面科学表征方法的性质和操作限制所造成的，几十年来一直是阻碍该领域进步的障碍。幸运的是，正如本期评论所表明的那样，该领域研究人员的思维方式在过去几十年中发生了巨大变化。在本虚拟专题中，我们全面概述了热催化和电催化原位和操作研究的最新进展。此外，我们还提供对该领域未来发展的见解。催化剂本质上是动态材料，能够响应各种环境因素或刺激（例如温度、压力、电势、气体和/或液体成分以及反应时间）而发生转变。这些波动深刻地影响催化剂与气相和液相之间的相互作用，从而影响催化材料的表面和本体结构和性能。 因此，掌握这种复杂的相互作用至关重要，以促进对新型催化材料的知识驱动型探索，查明与催化活性直接相关的结构特征，同时突破时间和空间分辨率的界限。 (1−3) 结构现象对催化剂性能起着至关重要的作用。它们确定活性位点的电子局部特性，控制其动态外观和再生，并在更大的长度尺度上影响分子和能量的传输特性。分子光谱与红外光谱一样，可以为分子反应和环境条件引起的变化提供有价值的见解。 (4) 另一方面，中子散射虽然不太常用，但却为轻元素提供了异常精确的结构信息，有效地补充了基于 X 射线和光子的技术。 (5)固液界面反应变得越来越重要，特别是在电催化领域。液体细胞透射电子显微镜、(2) 扫描电化学探针显微镜、(6) X 射线散射、(7) 和 X 射线计算机断层扫描 (8) 等技术提供了对外表面和内表面的重要见解，有助于量化电极纹理、形态和弯曲度。这些评估有时将空间尺度联系起来，只有共同才能描述催化过程的运行模式。操作结果对于理解催化剂的演变和动力学及其在操作过程中的失活/结垢至关重要。 鉴于固液界面物质的复杂性质，像和频生成这样的高度灵敏和选择性的技术对于报告其分子信息是必不可少的。 (9) 同样，理解光催化现象是一个日益重要的挑战。 (3) 尽管如此，尽管最近取得了巨大进展，但应该认识到，利用当前可用的反应器和光谱仪组合并不总是能够实现真正的操作表征。此外，必须致力于克服当前的时间分辨率障碍以及与多长度尺度催化剂表征或同时光谱显微镜分析相关的大量额外工作，以获得有关催化剂形态、结构和组成的空间分辨信息。在这里，人工智能在实时数据分析和深度自动化方面的应用可能会在收集统计相关数量的信息和更广泛的实验条件方面带来突破，而这些条件在今天通过资源分配的实践受到严格限制。在获得的无数实验数据中，总是需要将观众与活跃物种分开，这要求实验和理论小组的密切互动。这种合作的先决条件是通过稳态同位素瞬态动力学分析（SSITKA）或其他周期性扰动技术（例如调制激发光谱（MES））获取动力学解析数据。这些实验只能在真正的反应器中进行，该反应器的特点是在实验中施加的压力条件下具有气体动力学行为。 目前的操作方法存在缺陷，除了转换值之外，动力学数据的缺乏表明，当它们与实验条件无关时，其价值有限。操作方法的未来发展可能会更加重视通过与光谱或成像信息类似的审查来评估动力学信息。尽管在电催化实验中，液体电解质的存在将压力（化学势）固定在实际条件下，但热催化实验的情况并不常见。在这里，要么在实际压力下的实验具有有限的表面敏感性，要么在性能压力下表面敏感的实验要求非常高。模型纳米结构系统的应用是一种常见的出路，但如果要分析相关性能（工业相关）系统的行为，则需要仔细论证。在将操作结果外推到“真实”反应堆运行时，在操作条件下获得的动力学参数将成为在压力和材料复杂性方面一直弥合实验差距的证据。毕竟，测量由催化剂、反应物和反应器组成的催化系统的稳态动力学仍然是催化研究中最灵敏的“光谱仪”。最后，马克斯·普朗克明智地指出“应用必须先于承认”。本期精美地展示了我们现在可以“识别”的实验工具的气息，即深入了解催化材料在工作时的复杂性。 只有当至少部分复杂性被揭示出来时，人们才能考虑将这些知识转化为可持续社会急需的应用。 Beatriz Roldán Cuenya 目前是德国柏林马普学会弗里茨-哈伯研究所界面科学系主任。她是德国柏林工业大学、柏林自由大学和波鸿鲁尔大学的名誉教授。此外，她还是中佛罗里达大学（美国）的杰出研究教授。她于 1998 年在奥维耶多大学（西班牙）获得了物理学硕士/学士学位，随后又获得了博士学位。 2001年获得杜伊斯堡-埃森大学（德国）物理学博士学位。2001年至2003年在美国加州大学圣塔芭芭拉分校进行化学工程博士后研究。 2004 年，她加入中佛罗里达大学物理系担任助理教授，并于 2012 年成为正教授。2013 年，Roldán Cuenya 教授回到德国，担任鲁尔大学固体物理学讲座教授她一直待在波鸿，直到 2017 年加入 FHI。Roldán Cuenya 教授的研究项目探索纳米结构的物理和化学性质，重点是基于操作微观和光谱表征的热催化和电催化方面的进展。 Miguel A. Bañares 担任位于西班牙马德里的 CSIC 催化与石油化学研究所的全职研究教授。此前，他曾担任西班牙国家研究委员会 CSIC 的副总裁。 巴尼亚雷斯小组进行的研究重点是阐明催化中的结构-性能关系。他们通过将光谱学与催化反应过程中的同步活性测量相结合来实现这一目标，这种方法被称为“operando” ，他在 2002 年创造了这个术语。为了表彰他开创性的“operando”方法论工作，Bañares 被授予荣誉博士学位，即荣誉博士 (Doctor Honoris Causa)。法国卡昂诺曼底大学。他获得了理学学士和博士学位。拥有西班牙萨拉曼卡大学的学位。本文引用了其他 9 篇出版物。这篇文章尚未被其他出版物引用。本文参考了其他 9 篇出版物。