Article
Chemistry, Physical
Begona Sellers-Anton, Esther Bailon-Garcia, Arantxa Davo-Quinonero, Dolores Lozano-Castello, Agustin Bueno-Lopez
Summary: PrOx nanoparticles exhibit high catalytic activity in soot combustion, attributed to their high surface area, low crystal size, and improved reducibility. After aging, PrOx nanoparticles maintain high activity compared to other aged catalysts, highlighting their superior performance in long-term stability.
APPLIED SURFACE SCIENCE
(2021)
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
Anna Cooper, Stan Golunski, Stuart H. Taylor
Summary: The addition of potassium to the catalyst has an impact on the relationship between NOx reduction and soot oxidation. Lower potassium loadings can promote NOx reduction without affecting soot oxidation, while higher loadings almost completely disable NOx reduction and only contribute to the activity of the catalyst in the presence of soot. At a loading of 20% potassium, the potassium phase segregates, exposing other reaction sites.
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
Sabrina Ballauri, Enrico Sartoretti, Chiara Novara, Fabrizio Giorgis, Marco Piumetti, Debora Fino, Nunzio Russo, Samir Bensaid
Summary: Catalytic oxidation is an effective technology for controlling methane emissions. Palladium-based catalysts supported on cerium-praseodymium mixed oxides exhibit improved activity and stability.
Article
Chemistry, Physical
Meng Wang, Yan Zhang, Yunbo Yu, Wenpo Shan, Hong He
Summary: This study successfully developed a 10%Cs/3%Co/Ce0.5Sn0.5O2 catalyst with outstanding soot oxidation performance for diesel soot oxidation. The significant improvement in catalyst performance was attributed to the doping of Cs, which lowered the T-50 of the catalyst and increased oxygen activity.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Multidisciplinary
Igor Yu Kaplin, Ekaterina S. Lokteva, Svetlana Bataeva, Konstantin Maslakov, Alexander Fionov, Alexey Shumyantsev, Oksana Ya Isaikina, Alexey O. Kamaev, Elena Golubina
Summary: The study analyzed the effects of template nature and MnOx modification on the catalytic efficiency of Ce0.8Zr0.2O2 (CZ) catalysts in CO oxidation and soot oxidation. The results showed that CZ(SD) had better catalytic activity in CO oxidation than CZ(CTAB) due to its biomorphic texture and improved oxygen mobility, while CZ(SD) had lower efficiency in soot oxidation due to low surface reducibility. Despite differences in structure and interaction, Mn-modified catalysts exhibited similar catalytic properties, with enhanced performance in CO oxidation but worse performance in soot oxidation compared to CZ(CTAB).
PURE AND APPLIED CHEMISTRY
(2021)
Article
Energy & Fuels
Jiangjun Wei, Chenyang Fan, Yuan Zhuang, Zheng Fu, Ze Guan, Haizhao Li, Deliang Li, Yejian Qian
Summary: The mechanism of soot catalytical oxidation was investigated through various experiments, including temperature-programmed-oxidation (TPO), X-ray photoelectron spectroscopy, Fourier Transform Infrared Spectrometer, and Raman scattering spectrometer. It was found that ceria catalyst enhances the consumption of amorphous carbon and improves the structure and composition of soot surface, facilitating the oxidation reactions.
Article
Chemistry, Applied
J. C. Martinez-Munuera, V. M. Serrano-Martinez, J. Gimenez-Manogil, M. P. Yeste, A. Garcia-Garcia
Summary: This research aimed to study the nature of active sites and synergies in copper/ceria-zirconia formulations for low temperature CO oxidation by creating copper entities with different properties. Results showed that increasing copper loading up to 2% led to gradual improvements in activity and reducibility. The preparation method was identified as a critical variable in catalytic performance, with the IWI method showing superior results.
Article
Chemistry, Physical
Juan Carlos Martinez-Munuera, Marina Cortes-Reyes, Avelina Garcia-Garcia
Summary: This research investigates the behavior of different ceria-praseodymia mixed oxides and model catalysts in interaction with 18O2 under different temperatures, simulating conditions in gasoline direct injection (GDI) exhaust gases. The capacity of oxygen activation and uptake varies depending on the catalyst, temperature, praseodymium content, and preparation method. Some ceria-praseodymia formulations show high soot combustion activity, with the involvement of active oxygen species after the 18O2 pulse.
APPLIED CATALYSIS B-ENVIRONMENTAL
(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, Applied
Enrico Sartoretti, Chiara Novara, Angelica Chiodoni, Fabrizio Giorgis, Marco Piumetti, Samir Bensaid, Nunzio Russo, Debora Fino
Summary: In this study, novel ceria-based nanocatalysts containing different quantities of La and Nd were prepared and their structural and physico-chemical properties were examined. Doping with La and Nd altered the morphology and oxygen deficiency of ceria and affected the catalytic activity towards CO, NO, and soot oxidation. Among them, the Ce-La equimolar oxide exhibited outstanding performances due to its optimal morphology and surface acidity.
Article
Chemistry, Physical
Lioudmila Nossova, Gianni Caravaggio
Summary: The study investigated the effectiveness of silver-zirconia catalysts doped with Y, La, Ce and Pr for soot oxidation under low O2 concentration, relevant to gasoline direct injection engine conditions. The Ag/La-ZrO2 catalyst showed the best catalytic performance, with a Tmax of 405°C for a fresh sample and 420°C after aging at 700°C for 6 hours. Additionally, the doped catalysts exhibited improved co-oxidation activity for CO and C3H6. The Ag/ZrO2 catalyst benefited from the synergy between silver particles and doped zirconia.
CATALYSIS COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Begona Sellers-Anton, Esther Bailon-Garcia, Arantxa Davo-Quinonero, Dolores Lozano-Castello, Agustin Bueno-Lopez
Summary: A Ce(0.5)Pr(0.5)Ox soot combustion catalyst with both high activity and thermal stability has been developed by combining Ce(0.5)Pr(0.5)Ox nanoparticles and MS-macroporous structures. The hybrid catalyst showed a significant decrease in soot combustion temperature compared to the uncatalyzed reaction, and the thermal aging only slightly affected its performance. The Ce(0.5)Pr(0.5)Ox nanoparticles provided high activity, while the MS structure improved the contact between the catalyst and soot particles.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Environmental
M. Pilar Orihuela, Paolo Miceli, Joaquin Ramirez-Rico, Debora Fino, Ricardo Chacartegui
Summary: This study utilized biomorphic silicon carbide to fabricate a wall-flow filter with ceria-based catalytic coatings of two different morphologies, demonstrating a reduction in regeneration temperature and enhanced soot oxidation. The influence of substrate arrangement on regeneration performance and oxidative capacity of the coating was analyzed, offering possibilities for further reducing soot oxidation temperature through engineered ceria morphology and optimal substrate arrangement.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Nanoscience & Nanotechnology
Giuseppe Ferraro, M. Mar Bernal, Fabio Carniato, Chiara Novara, Mauro Tortello, Silvia Ronchetti, Fabrizio Giorgis, Alberto Fina
Summary: Thermally conductive nanopapers fabricated from graphene and related materials have great potential in thermal management applications. The use of bifunctional polyaromatic molecules is found to address the problem of ineffective thermal contacts within the nanopapers. The non-covalent functionalization with bispyrene compounds significantly enhances the thermal diffusivities of the nanopapers.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Barbara Bonelli, Olimpia Tammaro, Ferenc Martinovic, Roberto Nasi, Gianfranco Dell'Agli, Paola Rivolo, Fabrizio Giorgis, Nicoletta Ditaranto, Fabio Alessandro Deorsola, Serena Esposito
Summary: MnOx-TiO2 catalysts prepared by the reverse micelle-assisted sol-gel method exhibit good dispersion and catalytic activity, with a high NOx conversion rate of up to 90% at low Mn loading compared to impregnated catalysts.
Article
Chemistry, Applied
Sabrina Ballauri, Enrico Sartoretti, Chiara Novara, Fabrizio Giorgis, Marco Piumetti, Debora Fino, Nunzio Russo, Samir Bensaid
Summary: Catalytic oxidation is an effective technology for controlling methane emissions. Palladium-based catalysts supported on cerium-praseodymium mixed oxides exhibit improved activity and stability.
Article
Chemistry, Applied
Enrico Sartoretti, Chiara Novara, Angelica Chiodoni, Fabrizio Giorgis, Marco Piumetti, Samir Bensaid, Nunzio Russo, Debora Fino
Summary: In this study, novel ceria-based nanocatalysts containing different quantities of La and Nd were prepared and their structural and physico-chemical properties were examined. Doping with La and Nd altered the morphology and oxygen deficiency of ceria and affected the catalytic activity towards CO, NO, and soot oxidation. Among them, the Ce-La equimolar oxide exhibited outstanding performances due to its optimal morphology and surface acidity.
Article
Chemistry, Analytical
Niccolo Paccotti, Alessandro Chiado, Chiara Novara, Paola Rivolo, Daniel Montesi, Francesco Geobaldo, Fabrizio Giorgis
Summary: This study aimed to synthesize silver nanoparticles on porous silicon surfaces using microfluidic technology to achieve fine control over the morphology and spatial distribution of the nanostructures. By adjusting synthesis parameters such as precursor concentration, temperature, and flow rate, the effects on the morphology of silver nanoparticles were investigated. The results showed that variations in flow rate affected the uniformity of SERS enhancement, while an increase in temperature or silver precursor concentration led to higher SERS efficiency through the production of larger nanoparticles.
Article
Chemistry, Physical
Melodj Dosa, Miguel Jose Marin-Figueredo, Enrico Sartoretti, Chiara Novara, Fabrizio Giorgis, Samir Bensaid, Debora Fino, Nunzio Russo, Marco Piumetti
Summary: In this study, a series of CuCeOx catalysts were prepared and their catalytic performances in CO and ethene oxidation reactions were investigated. The 20%CuCeOx catalyst exhibited the best catalytic properties in both reactions.
Article
Chemistry, Physical
Sabrina Ballauri, Enrico Sartoretti, Min Hu, Carmine D'Agostino, Zijuan Ge, Liang Wu, Chiara Novara, Fabrizio Giorgis, Marco Piumetti, Debora Fino, Nunzio Russo, Samir Bensaid
Summary: This study presents an improved design for Pd/Ce-Pr catalysts, showing that the PdO-PrOx interaction in materials with high praseodymium content results in lower activity, while a limited amount of Pr in ceria can lead to a more active catalyst. The simultaneous presence of Pd in its reduced and oxidized forms is a key factor for high activity, and the higher hydrophobicity of the sample significantly reduces the H2O inhibition effect typical of Pd-based materials.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Food Science & Technology
Silvia Grassi, Alessandro Giraudo, Chiara Novara, Nicola Cavallini, Francesco Geobaldo, Ernestina Casiraghi, Francesco Savorani
Summary: A method combining FT-NIR spectroscopy and chemometric modelling was investigated to obtain real-time knowledge about the roasting effects on coffee's chemical-physical composition. In-line spectra were acquired by inserting a NIR probe into a laboratory coffee roaster, and MCR-ALS was used to model the chemical-physical changes during the roasting process. The proposed approach provides the groundwork for direct real-time implementation of automated monitoring of the roasting process at industrial scale.
FOOD ANALYTICAL METHODS
(2023)
Article
Chemistry, Physical
Chiara Novara, Daniel Montesi, Sofia Bertone, Niccolo Paccotti, Francesco Geobaldo, Marwan Channab, Angelo Angelini, Paola Rivolo, Fabrizio Giorgis, Alessandro Chiado
Summary: This study investigates the impact of probe labelling configuration on the sensitivity of SERS-based bioassays for miRNA quantitation. The results show that at high concentration of miRNA, locating the Raman reporters closer to the plasmonic surface significantly increases the SERS intensity. However, at low miRNA concentration, the SERS intensity levels off.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Applied
Clarissa Cocuzza, Enrico Sartoretti, Chiara Novara, Fabrizio Giorgis, Samir Bensaid, Nunzio Russo, Debora Fino, Marco Piumetti
Summary: A set of Cu-Mn oxides was synthesized using solution combustion synthesis method with varying copper and manganese ratios. The physico-chemical properties of the samples were investigated with various techniques, and the catalysts were tested for total VOC oxidation. The best performance was achieved with a copper content ranging from 15 at % to 45 at%, and the catalysts exhibited good stability and low water vapor inhibition.
Article
Chemistry, Applied
Enrico Sartoretti, Chiara Novara, Maria Cristina Paganini, Mario Chiesa, Micaela Castellino, Fabrizio Giorgis, Marco Piumetti, Samir Bensaid, Debora Fino, Nunzio Russo
Summary: Copper-ceria mixed oxides are considered promising catalysts for oxidation reactions, but their mechanistic understanding is still incomplete. In this study, pure and Cu-doped ceria samples were investigated through spectroscopic techniques, revealing the role of different copper sites and lattice defects. Cu+ species and Cu0 clusters promote CO adsorption at low temperature, while isolated Cu2+ monomers and dimers enhance lattice oxygen mobility. Changes in the structure of Cu-doped ceria occur during CO oxidation, but can be reversed and reorganized in the presence of O2. The excellent performance of Cu-doped ceria originates from the cooperation among different catalytic sites in the mixed oxide.
