The applications of copper (Cu) and Cu-based nanoparticles, which are based on the earth-abundant and inexpensive copper metal, have generated a great deal of interest in recent years, especially in the field of catalysis. The possible modification of the chemical and physical properties of these nanoparticles using different synthetic strategies and conditions and/or via postsynthetic chemical treatments has been largely responsible for the rapid growth of interest in these nanomaterials and their applications in catalysis. In addition, the design and development of novel support and/or multimetallic systems (e.g., alloys, etc.) has also made significant contributions to the field. In this comprehensive review, we report different synthetic approaches to Cu and Cu-based nanoparticles (metallic copper, copper oxides, and hybrid copper nanostructures) and copper nanoparticles immobilized into or supported on various support materials (SiO2, magnetic support materials, etc.), along with their applications i...

http://pubs.acs.org/doi/pdfplus/10.1021/acs.chemrev.5b00482

Cu and Cu-Based Nanoparticles: Synthesis and Applications in Catalysis.

Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

Complex Hydrides for Hydrogen Storage

Carbon dioxide (CO2) capture using solid sorbents has been recognized as a very promising technology that has attracted intense attention from both academic and industrial fields in the last decade. It is astonishing that around 2000 papers have been published from 2011 to 2014 alone, which is less than three years after our first review paper in this journal on solid CO2 sorbents was published. In this short period, much progress has been made and the major research focus has more or less changed. Therefore, we feel that it is necessary to give a timely update on solid CO2 capture materials, although we still have to keep some important literature results published in the past years so as to keep the good continuity. We believe this work will benefit researchers working in both academic and industrial areas. In this paper, we still organize the CO2 sorbents according to their working temperatures by classifying them as such: (1) low-temperature ( 400 °C). Since the sorption capacity, kinetics, recycling stability and cost are important parameters when evaluating a sorbent, these features will be carefully considered and discussed. In addition, due to the huge amounts of cost-effective CO2 sorbents demanded and the importance of waste resources, solid CO2 sorbents prepared from waste resources and their performance are reviewed. Finally, the techno-economic assessments of various CO2 sorbents and technologies in real applications are briefly discussed.

Recent advances in solid sorbents for CO2 capture and new development trends

Oxidation into CO2 is a major solution to CO abatement in air depollution treatments. The development of catalytic converters led to an extraordinary high number of publications on metal catalysts during the last fifty years. Due to the increasing price of noble metals and to remarkable progresses in oxide syntheses, catalytic oxidation of carbon monoxide over oxide catalysts has recently gained in interest, even if some oxides are known to present remarkable activity since the beginning of the 20th century. In this Review, the kinetics and mechanism of CO oxidation on single and mixed oxides are examined, alongside the catalyst structures

Catalytic Oxidation of Carbon Monoxide over Transition Metal Oxides

The chemical transformation of CO2 not only mitigates the anthropogenic CO2 emission into the Earth’s atmosphere but also produces carbon compounds that can be used as precursors for the production of chemicals and fuels. The activation and conversion of CO2 can be achieved on multifunctional catalytic sites available at the metal/oxide interface by taking advantage of the synergy between the metal nanoparticles and oxide support. Herein, we look at the recent progress in mechanistic studies of CO2 hydrogenation to C1 (CO, CH3OH, and CH4) compounds on metal/oxide catalysts. On this basis, we are able to provide a better understanding of the complex reaction network, grasp the capability of manipulating structure and combination of metal and oxide at the interface in tuning selectivity, and identify the key descriptors to control the activity and, in particular, the selectivity of catalysts. Finally, we also discuss challenges and future research opportunities for tuning the selective conversion of CO2 on ...

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Tuning Selectivity of CO2 Hydrogenation Reactions at the Metal/Oxide Interface

Role of surface Ni and Ce species of Ni/CeO 2 catalyst in CO 2 methanation

CO oxidation over CuO/Ce1−xCuxO2−δ and Ce1−xCuxO2−δ catalysts: Synergetic effects and kinetic study

Ce0.9Pr0.1O2-δ, Ce0.95Cu0.05O2-δ, and Ce0.9Pr0.05Cu0.05O2-δ mixed oxides and pure CeO2 were prepared with a sol−gel method and were characterized by XRD, in situ Raman, and in situ DRIFTS techniques. The XRD results confirmed the formation of Ce−Pr−O solid solution. The Raman results indicated that a higher concentration of oxygen vacancies was obtained on the Pr-doped samples compared to the Ce0.95Cu0.05O2-δ and pure CeO2 samples. Surface chemical states of the Ce0.9Pr0.1O2-δ and Ce0.9Pr0.05Cu0.05O2-δ mixed oxides were determined by in situ Raman spectroscopy, which indicated that the surfaces of the two mixed oxides were both close to oxidation state during the reaction, despite of the presence of reducing reactant CO in the gas mixture. The in situ DRIFTS results evidenced the chemisorption of CO in the Cu-containing samples. The catalysts were tested for CO oxidation, and it was found that the enhanced reactivity was closely related to the higher concentrations of the oxygen vacancies and the chemisor...

Enhanced Activity for CO Oxidation over Pr- and Cu-Doped CeO2 Catalysts: Effect of Oxygen Vacancies

A series of CuO/CeO2 and inverse CeO2/CuO catalysts were prepared by an incipient wetness impregnation method and tested for CO oxidation. Crystallite sizes of CeO2 and CuO were evaluated by X-ray diffraction and N2O chemisorption, as well as transmission electron microscopy. It was found that a CuO(5)/CeO2-500 catalyst with a CuO crystallite size of 4.1 nm and a CeO2(5)/CuO-500 catalyst with a CeO2 crystallite size of 4.0 nm had identical activities, indicating that the reaction may occur at the interface of CuO−CeO2. According to the turnover frequency based on CuO sites located on the CuO−CeO2 interface, the activity on the larger CuO crystallite was much higher than that on the smaller one, indicating that CuO−CeO2 catalyst for CO oxidation is structure-sensitive. The enhanced activity was ascribed to a higher density of chemisorbed CO on the active sites for the larger CuO crystallite.

Study of Catalytic Activity at the CuO−CeO2 Interface for CO Oxidation

The PdO/Ce1–xPdxO2−δ catalyst prepared by a solution-combustion method contained free surface PdO species and PdO species in Ce1–xPdxO2−δ solid solution, whereas the PdO/CeO2 catalyst prepared by an impregnation method contained only free surface PdO species. The free surface PdO species could be removed by nitric acid. Contributions of the PdO species to catalytic CO oxidation were quantitatively evaluated. The free surface PdO species in the PdO/Ce1–xPdxO2−δ catalyst had the highest activity (969.3 μmolCO gPd–1 s–1), those in the PdO/CeO2 catalyst had medium activity (109.0 μmolCO gPd–1 s–1), and the PdO species in the Ce1–xPdxO2−δ solid solution had the lowest activity (13.2 μmolCO gPd–1 s–1). Synergetic effects of PdO species were responsible for the enhanced reactivity of the PdO/Ce1–xPdxO2−δ catalyst, as the free surface PdO species provided CO chemisorption sites and the Ce1–xPdxO2−δ solid solution generated more oxygen vacancies for oxygen activation.

Ai-Ping Jia

Papers

Role of surface Ni and Ce species of Ni/CeO 2 catalyst in CO 2 methanation

CO oxidation over CuO/Ce1−xCuxO2−δ and Ce1−xCuxO2−δ catalysts: Synergetic effects and kinetic study

Enhanced Activity for CO Oxidation over Pr- and Cu-Doped CeO2 Catalysts: Effect of Oxygen Vacancies

Study of Catalytic Activity at the CuO−CeO2 Interface for CO Oxidation

Synergetic Effects of PdO Species on CO Oxidation over PdO–CeO2 Catalysts