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Xin-Pu Fu

Bio: Xin-Pu Fu is an academic researcher from Shandong University. The author has contributed to research in topics: Catalysis & Oxide. The author has an hindex of 15, co-authored 27 publications receiving 603 citations. Previous affiliations of Xin-Pu Fu include National University of Singapore.

Papers
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Journal ArticleDOI
TL;DR: It is found that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction.
Abstract: Small-size (<5 nm) gold nanostructures supported on reducible metal oxides have been widely investigated because of the unique catalytic properties they exhibit in diverse redox reactions. However, arguments about the nature of the gold active site have continued for two decades, due to the lack of comparable catalyst systems with specific gold species, as well as the scarcity of direct experimental evidence for the reaction mechanism under realistic working conditions. Here we report the determination of the contribution of single atoms, clusters and particles to the oxidation of carbon monoxide at room temperature, by the aid of in situ X-ray absorption fine structure analysis and in situ diffuse reflectance infrared Fourier transform spectroscopy. We find that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction. Nanoscale supported gold clusters are common redox catalysts but in many cases the nature of the active sites remains unclear. Here, the authors use X-ray absorption to determine the contribution of single gold atoms, clusters and particles on the reactivity of room-temperature carbon monoxide oxidation.

142 citations

Journal ArticleDOI
TL;DR: A very clear image of the surface reaction for the WGS reaction catalyzed by the gold-ceria catalyst is obtained and it is proved that the reaction between bridged surface -OH groups and CO molecules adsorbed on interfacial Au atoms contributes dominantly to the W GS reactivity.
Abstract: The crucial role of the metal–oxide interface in the catalysts of the water–gas shift (WGS) reaction has been recognized, while the precise illustration of the intrinsic reaction at the interfacial site has scarcely been presented. Here, two kinds of gold–ceria catalysts with totally distinct gold species, <2 nm clusters and 3 to 4 nm particles, were synthesized as catalysts for the WGS reaction. We found that the gold cluster catalyst exhibited a superiority in reactivity compared to gold nanoparticles. With the aid of comprehensive in situ characterization techniques, the bridged −OH groups that formed on the surface oxygen vacancies of the ceria support are directly determined to be the sole active configuration among various surface hydroxyls in the gold–ceria catalysts. The isotopic tracing results further proved that the reaction between bridged surface −OH groups and CO molecules adsorbed on interfacial Au atoms contributes dominantly to the WGS reactivity. Thus, the abundant interfacial sites in g...

119 citations

Journal ArticleDOI
TL;DR: In this paper, a nonoxide/hydroxide material, atomically dispersed dual-metal catalysts for CO oxidation reaction, is presented, which is based on a non-oxide/oxide/oxide material with multicomponent active sites.
Abstract: Catalysts for CO oxidation reaction are mainly based on oxide/hydroxide materials with multicomponent active sites. Here, we report a nonoxide/hydroxide material, atomically dispersed dual-metal si...

102 citations

Journal ArticleDOI
TL;DR: Based on a comprehensive structural characterization and mechanistic study, the copper atoms with unsaturated coordination in the form of Cu1O3 were identified to be the sole active site, at which both CO and O2 molecules were activated, thus inducing remarkable CO oxidation activity with a very low copper loading.
Abstract: The construction of stable active site in nanocatalysts is of great importance but is a challenge in heterogeneous catalysis. Unexpectedly, coordination-unsaturated and atomically dispersed copper species were constructed and stabilized in a sintered copper-ceria catalyst through air-calcination at 800 °C. This sintered copper-ceria catalyst showed a very high activity for CO oxidation with a CO consumption rate of 6100 μmolCO·gCu-1·s-1 at 120 °C, which was at least 20 times that of other reported copper catalysts. Additionally, the excellent long-term stability was unbroken under the harsh cycled reaction conditions. Based on a comprehensive structural characterization and mechanistic study, the copper atoms with unsaturated coordination in the form of Cu1O3 were identified to be the sole active site, at which both CO and O2 molecules were activated, thus inducing remarkable CO oxidation activity with a very low copper loading (1 wt %).

87 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a method to synthesize organonitrogen chemicals such as amines, nitriles, amides, amino acids, and N-heterocycles.
Abstract: Organonitrogen chemicals, such as amines, nitriles, amides, amino acids, and N-heterocycles, are ubiquitous building blocks in chemical industry. Conventional methodologies to prepare these chemica...

78 citations


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TL;DR: This Review will compare the results obtained from different systems and try to give a picture on how different types of metal species work in different reactions and give perspectives on the future directions toward better understanding of the catalytic behavior of different metal entities in a unifying manner.
Abstract: Metal species with different size (single atoms, nanoclusters, and nanoparticles) show different catalytic behavior for various heterogeneous catalytic reactions. It has been shown in the literature that many factors including the particle size, shape, chemical composition, metal–support interaction, and metal–reactant/solvent interaction can have significant influences on the catalytic properties of metal catalysts. The recent developments of well-controlled synthesis methodologies and advanced characterization tools allow one to correlate the relationships at the molecular level. In this Review, the electronic and geometric structures of single atoms, nanoclusters, and nanoparticles will be discussed. Furthermore, we will summarize the catalytic applications of single atoms, nanoclusters, and nanoparticles for different types of reactions, including CO oxidation, selective oxidation, selective hydrogenation, organic reactions, electrocatalytic, and photocatalytic reactions. We will compare the results o...

2,700 citations

Journal ArticleDOI
01 Jun 2018
TL;DR: A review of single-atom catalysts can be found in this paper, where the authors discuss the utility of SACs in a broad scope of industrially important reactions and highlight the advantages these catalysts have over those presently used.
Abstract: Single-atom catalysis has arguably become the most active new frontier in heterogeneous catalysis. Aided by recent advances in practical synthetic methodologies, characterization techniques and computational modelling, we now have a large number of single-atom catalysts (SACs) that exhibit distinctive performances for a wide variety of chemical reactions. This Perspective summarizes recent experimental and computational efforts aimed at understanding the bonding in SACs and how this relates to catalytic performance. The examples described here illustrate the utility of SACs in a broad scope of industrially important reactions and highlight the advantages these catalysts have over those presently used. SACs have well-defined active centres, such that unique opportunities exist for the rational design of new catalysts with high activities, selectivities and stabilities. Indeed, given a certain practical application, we can often design a suitable SAC; thus, the field has developed very rapidly and afforded promising catalyst leads. Moreover, the control we have over certain SAC structures paves the way for designing base metal catalysts with the activities of noble metal catalysts. It appears that we are entering a new era of heterogeneous catalysis in which we have control over well-dispersed single-atom active sites whose properties we can readily tune. Single-atom catalysts are heterogeneous materials featuring active metals sites atomically dispersed on a surface. This Review describes methods by which we prepare and characterize these materials, as well as how we can tune their catalytic performance in a variety of important reactions.

2,306 citations

Journal ArticleDOI
TL;DR: This review first briefly summarizes this background of MOF nanoparticle catalysis and then comprehensively reviews the fast-growing literature reported during the last years.
Abstract: Metal-organic framework (MOF) nanoparticles, also called porous coordination polymers, are a major part of nanomaterials science, and their role in catalysis is becoming central. The extraordinary variability and richness of their structures afford engineering synergies between the metal nodes, functional linkers, encapsulated substrates, or nanoparticles for multiple and selective heterogeneous interactions and activations in these MOF-based nanocatalysts. Pyrolysis of MOF-nanoparticle composites forms highly porous N- or P-doped graphitized MOF-derived nanomaterials that are increasingly used as efficient catalysts especially in electro- and photocatalysis. This review first briefly summarizes this background of MOF nanoparticle catalysis and then comprehensively reviews the fast-growing literature reported during the last years. The major parts are catalysis of organic and molecular reactions, electrocatalysis, photocatalysis, and views of prospects. Major challenges of our society are addressed using these well-defined heterogeneous catalysts in the fields of synthesis, energy, and environment. In spite of the many achievements, enormous progress is still necessary to improve our understanding of the processes involved beyond the proof-of-concept, particularly for selective methane oxidation, hydrogen production, water splitting, CO2 reduction to methanol, nitrogen fixation, and water depollution.

1,233 citations

Journal ArticleDOI
Shufang Ji1, Yuanjun Chen1, Xiaolu Wang1, Zedong Zhang1, Dingsheng Wang1, Yadong Li1 
TL;DR: In this review, various synthetic strategies for the synthesis of SASC are summarized with concrete examples highlighting the key issues of the synthesis methods to stabilize single metal atoms on supports and to suppress their migration and agglomeration.
Abstract: Manipulating metal atoms in a controllable way for the synthesis of materials with the desired structure and properties is the holy grail of chemical synthesis. The recent emergence of single atomic site catalysts (SASC) demonstrates that we are moving toward this goal. Owing to the maximum efficiency of atom-utilization and unique structures and properties, SASC have attracted extensive research attention and interest. The prerequisite for the scientific research and practical applications of SASC is to fabricate highly reactive and stable metal single atoms on appropriate supports. In this review, various synthetic strategies for the synthesis of SASC are summarized with concrete examples highlighting the key issues of the synthesis methods to stabilize single metal atoms on supports and to suppress their migration and agglomeration. Next, we discuss how synthesis conditions affect the structure and catalytic properties of SASC before ending this review by highlighting the prospects and challenges for the synthesis as well as further scientific researches and practical applications of SASC.

629 citations

Journal ArticleDOI
TL;DR: A compositional encyclopedia of SACs is provided, celebrating the 10th anniversary of the introduction of this term, and examines the coordination structures and associated properties accessed through distinct single-atom-host combinations and relate them to their main applications in thermo-, electro-, and photocatalysis.
Abstract: Isolated atoms featuring unique reactivity are at the heart of enzymatic and homogeneous catalysts. In contrast, although the concept has long existed, single-atom heterogeneous catalysts (SACs) have only recently gained prominence. Host materials have similar functions to ligands in homogeneous catalysts, determining the stability, local environment, and electronic properties of isolated atoms and thus providing a platform for tailoring heterogeneous catalysts for targeted applications. Within just a decade, we have witnessed many examples of SACs both disrupting diverse fields of heterogeneous catalysis with their distinctive reactivity and substantially enriching our understanding of molecular processes on surfaces. To date, the term SAC mostly refers to late transition metal-based systems, but numerous examples exist in which isolated atoms of other elements play key catalytic roles. This review provides a compositional encyclopedia of SACs, celebrating the 10th anniversary of the introduction of this term. By defining single-atom catalysis in the broadest sense, we explore the full elemental diversity, joining different areas across the whole periodic table, and discussing historical milestones and recent developments. In particular, we examine the coordination structures and associated properties accessed through distinct single-atom-host combinations and relate them to their main applications in thermo-, electro-, and photocatalysis, revealing trends in element-specific evolution, host design, and uses. Finally, we highlight frontiers in the field, including multimetallic SACs, atom proximity control, and possible applications for multistep and cascade reactions, identifying challenges, and propose directions for future development in this flourishing field.

505 citations