Article
Chemistry, Multidisciplinary
Olga A. Bulavchenko, Tatyana N. Afonasenko, Alexey R. Osipov, Alena A. Pochtar, Andrey A. Saraev, Zahar S. Vinokurov, Evgeny Yu Gerasimov, Sergey Tsybulya
Summary: The study of Mn-Ce oxide catalysts active in CO oxidation revealed that the catalyst containing ca. 50 at.% Mn exhibited the best catalytic performance due to high specific surface area, formation of solid solution, and maximum content of the solid solution.
Article
Nanoscience & Nanotechnology
Alvin M. H. Lim, Hua Chun Zeng
Summary: This work focuses on exploring the production of ultrathin hollow ceria or other rare-earth metal oxides, presenting a novel synthetic protocol for making ultrathin mesoporous hollow spheres with a tunable shell thickness. The approach shows promise for better utilization of rare-earth metal elements in various technological applications, including the fabrication of singular or multicomponent rare-earth metal oxides with ultrathin hollow morphology and structural uniformity.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Ceramics
Igor Zagaynov, Ivan Shelepin, Anatoly A. Konovalov, Ekaterina A. Obraztsova, Alexander Naumkin, Alexey Bykov, Vladimir G. Leontiev
Summary: The Ceria-based solid solutions doped with Gd, Bi, and a third dopant were successfully synthesized using the co-precipitation method with ultrasonic treatment. The synthesized powders exhibited a cubic fluorite structure with an average particle size of 5-15 nm and a mesoporous structure with pore diameters of 2-5 nm. Among the solid solutions studied, the catalyst Gd0.05Bi0.15Mn0.20Ce0.60O2 showed the lowest oxidation temperature, indicating superior catalytic activity.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Inorganic & Nuclear
Na Sun, Linlin Xiang, Bingsen Zhuge, Erjie Kan, Nan Yu, Lei Li, Long Kuai
Summary: This study demonstrates an excellent and cost-effective Ni-Ce-Ox catalyst prepared by synchronous spray-pyrolysis, which shows excellent catalytic performance in low-temperature CO oxidation reactions. The optimized Ni incorporation leads to a significant decrease in T50 and higher CO conversion rate. Theoretical calculations reveal that the reduction in oxygen vacancy formation energy at Ni-Ce single-atom sites enhances the adsorption activation of CO molecules. Furthermore, the Ni-Ce-Ox catalyst prepared by synchronous spray-pyrolysis exhibits superior performance compared to the counterparts prepared by immersion and hydrothermal methods.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Applied
M. Angeles Stegmayer, Silvia Irusta, Eduardo E. Miro, Viviana G. Milt
Summary: Co, Ce and Co-Ce nanofibers were synthesized by electrospinning method and applied to gas-solid and solid-solid-gas reactions. Different activity trends were observed in CO oxidation and combustion of diesel soot, with Co-Ce nanofibers showing the highest activity for soot combustion and Co exhibiting the highest activity for CO oxidation. The temperature range for maximum combustion rate was narrow for soot combustion and wider for CO oxidation. The high activity for soot oxidation was attributed to multiple contact points between fibers and soot particles, while the trend observed for CO oxidation was related to the higher redox capacity of Co.
Article
Chemistry, Physical
Olga A. Bulavchenko, Tatyana N. Afonasenko, Alexey R. Osipov, Alena A. Pochtar, Andrey A. Saraev, Evgeny Yu. Gerasimov
Summary: A series of Mn-Ce oxide catalysts with different annealing conditions were synthesized and characterized, showing that catalysts annealed in air exhibited higher activity in CO oxidation reaction compared to those prepared in argon. The combination of MnxCe1-xO2-delta solid solution, amorphous and crystalline manganese oxides, as well as Mn cations in the form of Mn2+, Mn3+ and Mn4+ on the catalyst surface contribute to the catalytic performance.
Article
Chemistry, Multidisciplinary
Zhiwen Li, Yifei Zhang, Qike Jiang, Liangliang Xu, Zhong-Kang Han, Alfons Baiker, Gao Li
Summary: This study presents a synthetic strategy for preparing CuO-supported CuCeOx catalysts by calcination of a hydrotalcite precursor. The catalysts were characterized by various techniques, revealing the formation of a mesoporous catalyst consisting of well-dispersed CuO-supported CuCeOx clusters with a high population of oxygen vacancies. The as-prepared catalyst showed excellent catalytic performance in the reduction of NO by CO, attributed to its high oxygen defect concentration facilitating redox reactions.
Article
Chemistry, Applied
Yu'nan Li, Lin Gan, Rui Si
Summary: This study investigated the effect of tungsten oxide on copper-ceria catalysts for CO oxidation reaction. The introduction of tungsten oxide changed the metal-support interaction and impaired the catalytic activity of copper-ceria catalysts for CO oxidation reaction. Various characterization techniques were used to analyze the structural and textural changes in the catalysts.
JOURNAL OF RARE EARTHS
(2021)
Article
Engineering, Chemical
Feng Ju, Hao Ling, Chengyi Qian, Jiawei Bian
Summary: In this study, a H2S-pretreated Pd-based catalyst was used for CO catalytic oxidation, showing outstanding catalytic activity, sulfur resistance, and high stability. The PdSx catalyst exhibited superior catalytic activity compared to other Pd-based catalysts, enabling complete oxidation of CO at around 200 degrees C. During a long-term test, the PdSx catalyst showed good ability and maintained a CO conversion rate of 94.93% in the presence of 500 ppm SO2 for 300 hours, indicating excellent stability. The study also discusses the mechanisms of CO catalytic oxidation and sulfur resistance, providing insights for the design of sulfur-resistant catalysts.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Srisin Eaimsumang, Nuwong Chollacoop, Apanee Luengnaruemitchai, Stuart H. Taylor
Summary: This study demonstrates a simple hydrothermal synthesis approach for preparing CeO2-supported gold (Au) catalysts, which exhibit enhanced catalytic performance in oxidation reactions when the reducibility of CeO2 support increases and the number of adsorbed peroxide species on the support increases due to Au addition.
FRONTIERS IN CHEMISTRY
(2022)
Article
Chemistry, Physical
Mareike Liebertseder, Carina B. Maliakkal, Marlene Crone, Guelperi Nails, Maria Casapu, Jan-Dierk Grunwaldt, Michael Tuerk, Christian Kuebel, Claus Feldmann
Summary: TiO2-CeO2-Pt hollow nanospheres with uniform size distribution of Pt nanoparticles were successfully synthesized using a liquid-phase strategy. The catalytic properties of the hollow nanospheres were evaluated for CO oxidation and demonstrated promising activity and stability, suggesting their potential application as high-porosity catalyst materials.
Article
Engineering, Environmental
Yaeun Seo, Min Woo Lee, Hyun Jae Kim, Jin Woo Choung, ChangHo Jung, Chang Hwan Kim, Kwan-Young Lee
Summary: The study showed that doping with appropriate amounts of Ag can increase the oxygen storage capacity of the catalyst and form active Pd-0 species, leading to improved catalytic activity for the oxidation of CO and C3H6.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Ivan Surin, Zhenchen Tang, Julian Geiger, Suyash Damir, Henrik Eliasson, Mikhail Agrachev, Frank Krumeich, Sharon Mitchell, Vita A. Kondratenko, Evgenii V. Kondratenko, Gunnar Jeschke, Rolf Erni, Nuria Lopez, Javier Perez-Ramirez
Summary: The discovery of low-valent manganese stabilized on ceria as a stable catalyst for ammonia oxidation to nitrous oxide offers a promising solution to the high manufacturing costs and suboptimal selectivity and stability of nitrous oxide synthesis. The catalyst exhibits higher productivity than state-of-the-art alternatives and establishes a structure-performance relationship.
ADVANCED MATERIALS
(2023)
Article
Energy & Fuels
Jinfan Zhou, Di Wang, Ganxue Wu, Ningjie Fang, Xincheng Song, Jianjun Li, Junhui Chen, Yongjun Liu, Jiaxiu Guo, Yinghao Chu
Summary: A series of Co-CeOx monolith catalysts were synthesized by the citric acid sol-gel method to improve the catalytic combustion performance of toluene. Among them, Co1Ce2Ox showed optimal activity and thermal stability, potentially due to the strong interaction between Co and Ce enhancing the formation of oxygen vacancies, improving active oxygen mobility.
Article
Chemistry, Physical
Igor Zagaynov, Ivan Shelepin, Alexander Naumkin, Anatoly A. Konovalov
Summary: Ceria based solid solution catalysts were synthesized and studied for CO oxidation, with the addition of a small amount of iso/aliovalent dopants (Bi, Ti, Sn) resulting in increased catalytic activity. However, a further increase in dopant concentration may decrease activity due to the dilution of active surface with less active catalytic centers.
MOLECULAR CATALYSIS
(2022)
Article
Chemistry, Applied
Qingyuan Zheng, Jack H. Williams, Scott Elgersma, Mick D. Mantle, Andrew J. Sederman, G. Leendert Bezemer, Constant M. Guedon, Lynn F. Gladden
Summary: In this study, a pilot-scale fixed-bed reactor compatible with NMR/MRI was developed for Fischer-Tropsch synthesis. Multiple magnetic resonance techniques were applied to quantitatively characterize different product species within catalyst pellets, providing valuable information for catalyst and reactor optimization.
Article
Chemistry, Applied
Lisa Ramisch, Sebastian Pfaff, Sabrina M. Gericke, Edvin Lundgren, Johan Zetterberg
Summary: We present a combination of optical operando techniques that allow simultaneous measurement of adsorbed species on catalyst surfaces, monitoring of surface oxide formation, and imaging of the gas phase above the catalyst surface. The experimental setup was validated by studying CO oxidation on Pd(100) at different pressures, revealing the effects of pressure on the heterogeneous catalytic reaction.
Article
Chemistry, Applied
Marta Paniagua, Gabriel Morales, Juan A. Melero, Daniel Garcia-Salgado
Summary: The influence of common impurities in levulinic acid on the catalytic performance of different acid catalysts for bio-jet fuel production was studied. It was found that furfural had the greatest detrimental effect on catalyst performance, while propyl-sulfonic acid-modified SBA-15 and sulfonic acid resin Amberlyst-70 showed good regeneration ability.
Article
Chemistry, Applied
Jesus Tapiador, Pedro Leo, Guillermo Calleja, Gisela Orcajo
Summary: This study presents a new MOF material, Zn-URJC-13, with acid and basic sites, permanent porosity, and high affinity to CO2 molecules. The Zn-URJC-13 catalyst exhibits efficient performance in CO2 cycloaddition reactions and can be reused multiple times.
Article
Chemistry, Applied
Dan Zhao, Vita A. Kondratenko, Dmitry E. Doronkin, Shanlei Han, Jan-Dierk Grunwaldt, Uwe Rodemerck, David Linke, Evgenii V. Kondratenko
Summary: This study demonstrates the potential of cheap and commercially available Zr or Ti-based supports and ZnO to serve as active and selective catalysts for propane dehydrogenation (PDH). The catalytically active species formed in situ under PDH conditions consist of isolated ZnOx. ZnOx on the surface of LaZrOx shows the highest rate of propene formation.
Article
Chemistry, Applied
Hanbyeol Kim, Jung Rae Kim, Young-Kwon Park, Jeong-Myeong Ha, Jungho Jae
Summary: In this study, metal phosphates were used as catalysts for biomass conversion to produce sustainable aromatics through DielsAlder cycloaddition reactions. The effects of synthesis method, activation method, and P/Ti molar ratio on the structure and acid properties of titanium phosphate catalysts were systematically studied. The mesoporous titanium phosphate catalyst synthesized by hydrothermal method at 180℃ for 12 h followed by ethanol refluxing at 60℃ for 24 h at a molar P/Ti ratio of 1 showed the highest surface area and acid site density.
Article
Chemistry, Applied
Yasin Khani, Sumin Pyo, Kwang-Eun Jeong, Chul-Ung Kim, Moonis Ali Khan, Byong-Hun Jeon, Kun-Yi Andrew Lin, Siyoung Q. Choi, Young-Kwon Park
Summary: A protonated form of Zeolite Socony Mobil-5 (H-ZSM-5) catalyst was synthesized through a hydrothermal method using different sources of silica. The effect of loading the catalyst with yttrium, samarium, and gadolinium on the acidic properties was investigated. Among the metal-loaded catalysts, the Sm/LHZ catalyst showed the best performance in the methanol to propylene conversion due to its high amount of weak and intermediate acid sites, while the Gd-LHZ catalyst increased the selectivity towards ethane and propane.
Article
Chemistry, Applied
Michael Franc, Ivana Cisarova, Jan Vesely
Summary: The present study investigates an enantioselective cyclization of enals with imidazolone derivatives catalyzed by a combination of achiral Pd(0) complex and chiral secondary amine. Corresponding spirocyclic imidazolones were produced in high yields with moderate diastereoselectivity and excellent enantioselectivity. The developed co-operative catalytic methodology provides a highly substituted spirocyclic scaffold with four stereogenic centers under mild conditions.
Article
Chemistry, Applied
Mauro Alvarez, Jennifer Cueto, David P. Serrano, Pablo Marin, Salvador Ordonez
Summary: This study focuses on improving the formulation and preparation methods of catalysts for the production of dimethyl carbonate. By using suitable catalyst preparation methods and copper salt precursors, the researchers successfully produced catalysts with optimal performance for dimethyl carbonate formation.
Article
Chemistry, Applied
Claudia J. Keijzer, Luc C. J. Smulders, Dennie Wezendonk, Jan Willem de Rijk, Petra E. de Jongh
Summary: This study investigates the catalytic behavior of alpha-alumina supported silver catalysts in the presence of chloride. It is found that the particle size of silver can affect the selectivity of the catalyst, but different strategies lead to different results. In this size range, the selectivity of ethylene oxide is correlated to the Ag : Al2O3 surface ratio.
Article
Chemistry, Applied
Takeshi Aihara, Wataru Aoki, Michikazu Hara, Keigo Kamata
Summary: The development of acid-base bifunctional catalysts is important for promoting specific chemical transformations. In this study, Ti-based perovskite oxides were synthesized and used as catalysts for two C-C bond-forming reactions (cyanosilylation and Knoevenagel condensation). The highly pure SrTiO3 nanoparticles with a high specific surface area exhibited the highest catalytic performance, and could be easily recovered and reused.
Article
Chemistry, Applied
Olga Gorlova, Petra Pribylova, Eliska Vyskocilova, Katerina Peroutkova, Jan Kohout, Iva Paterova
Summary: This study investigates the Baeyer-Villiger oxidation of beta-cyclocitral using tin-modified mixed oxides as catalysts. The optimal reaction conditions and the effects of various factors on the reaction course and selectivity were determined. The results show that tin-modified mixed oxides exhibit high activity and selectivity in the oxidation reaction.
Article
Chemistry, Applied
M. I. Avila, M. M. Alonso-Doncel, L. Briones, G. Gomez-Pozuelo, J. M. Escola, D. P. Serrano, A. Peral, J. A. Botas
Summary: The catalytic fast pyrolysis of lignin using ion-exchanged zeolite catalysts showed significant improvements in bio-oil quality and the production of aromatic hydrocarbons and oxygenated compounds.
Article
Chemistry, Applied
Enrico Catizzone, Giorgia Ferrarelli, Paolo Bruno, Girolamo Giordano, Massimo Migliori
Summary: The acid-catalysed alcohol conversion reaction is a promising route for de-fossilization strategies. Research on pure alcohol conversion and simultaneous dehydration of mixed alcohols have shown different product compositions, with the type and distribution of acid sites affecting the reaction mechanism.
Article
Chemistry, Applied
Alireza Ranjbari, Juho Kim, Jihee Yu, Jiyun Kim, Mireu Park, Nayoung Kim, Kristof Demeestere, Philippe M. Heynderickx
Summary: This study investigated a novel kinetic model for the adsorption and photocatalytic degradation of methyl orange using commercial ZnO and reduced ZnO photocatalysts. The results provided new insights into the interaction of catalysts with molecules of different charges and compared with a previous study on methylene blue. The presence of oxygen vacancies in ZnO and their effects on adsorption and photocatalytic degradation were analyzed, and the photocatalytic degradation rate of reduced ZnO was found to increase significantly.