Article
Chemistry, Physical
Carlos Alberto Chagas, Martin Schmal
Summary: The effect of copper oxide species on the CuO-NiO/CeO2 structure and its influence on the preferential CO oxidation in H-2 excess reaction were investigated. The addition of Cu+ species increased the active sites and reduced the temperature of CO2 formation or selectivity. The stabilizing effect of carbonyl species inhibited the oxidation of H-2 and contributed to the superior selectivity towards CO2 at low temperatures.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Rodolfo M. Antoniassi, Arthur P. Machado, Ana Rita N. Paiva, Carla M. S. Queiroz, Jorge M. Vaz, Estevam Spinace, Julio Cesar M. Silva, Eduardo Carmine, Pedro H. C. Camargo, Roberto M. Torresi
Summary: An efficient Pt20Fe/CeO2 catalyst was synthesized using a simple borohydride reduction process, showing excellent CO conversion and CO2 selectivity at ambient temperature, meeting the requirements for hydrogen supply in fuel cell devices.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Zhenhua Zhang, Liping Fan, Weiqi Liao, Feiyue Zhao, Cen Tang, Jing Zhang, Ming Feng, Ji-Qing Lu
Summary: By studying the CO oxidation catalyzed by CeO2-CuO/Cu2O nanocomposites with different CuO structures, it was found that the CuO-CeO2 interfaces in the CeO2-CuO/c-Cu2O (cubes) nanocomposites exhibit higher intrinsic activity, indicating that the active oxygen species originates from CuO. An active 13.2% CeO2-CuO/c-Cu2O(s) catalyst for CO oxidation was achieved on fine Cu2O cubes, possessing a high density of active sites.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Physical
Magdalena Greluk, Wojciech Gac, Marek Rotko, Grzegorz Slowik, Sylwia Turczyniak-Surdacka
Summary: The addition of citric acid improved the dispersion and reduced particle size of metal particles, while catalysts prepared from ammonia solution showed the largest metal particle size. In steam reforming of ethanol, dehydrogenation of ethanol takes place preferentially on terrace sites, while cleavage of C-C bond is favored by edge/steps sites.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Hu Li, Fei-Xiang Tian, Qi Liu, Yi-Fan Han, Minghui Zhu
Summary: Copper-cerium catalysts are commonly used for the oxidation of CO. This study prepared CuO/CeInOx catalysts and found that the inclusion of In dopants improved the catalyst's activity. The Cu/Ce90In10Ox catalyst showed excellent CO oxidation activity at low temperatures.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Aggeliki Papavasiliou, Benedetta Oliani, Mirko Scanferla, Elias Sakellis, Antonella Glisenti, Paolo Canu, Fotis K. Katsaros
Summary: Mesoporous multicomponent materials based on alumina are synthesized through a facile evaporation-induced-self-assembly method. The addition of citric acid is found to be crucial in obtaining high mesoscopic order and notable homogeneity. After thermal aging, the distribution of metal oxides and nanoporous nature are well-preserved, with a parallel nucleation of ceria nanoparticles into the semi-crystalline framework. The catalytic activity is drastically enhanced, especially for the Cu-Ce-Al system, due to the material's structural reconstruction and its effect on metal-support interaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Multidisciplinary Sciences
Jan Meissner, Lara Ahrens, Joachim Pasel, Alexander Schwedt, Sebastian Wohlrab, Joachim Mayer, Ralf Peters
Summary: In this study, a method for directly coating monoliths with a CeO2/CuO catalyst using the urea-nitrate combustion method is presented. The catalyst was characterized and its catalytic activity for the preferential oxidation of CO was measured. The long-term stability of the catalyst was demonstrated in a 310-hour test. Direct coating is a promising approach to deposit a larger amount of catalyst onto the monolith in a single step.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Inorganic & Nuclear
Tanna Elyn Rodrigues Fiuza, Danielle Santos Goncalves, Daniela Zanchet
Summary: CeO2, when used as a promoter, enhances catalytic activity, but its impact on CeOx species and Cu reincorporation into the Au lattice in AuCu/SiO2 catalysts is crucial for the activity and stability of the CO-PROX reaction.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Zhihuan Qiu, Xiaolin Guo, Jianxin Mao, Renxian Zhou
Summary: This work provides a new strategy for eliminating trace CO in H-2-rich gas in a wide temperature range, using Co deposited CuO-CeO2 catalysts with a Co/(Cu + Ce) molar ratio of 1/1. The interactions between Cu, Co, and Ce species significantly affect the CO oxidation and CO methanation reactions, with different mechanisms dominating in low and high temperature ranges. Moreover, increasing the Co/(Cu + Ce) ratio from 1/2 to 1 enhances the low temperature CO-PROX catalytic performance.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Kang Wang, Yong Men, Wangwang Liu, Jingke Zhang
Summary: This review evaluates the current state and prospects of catalysts used for catalytical CO purification in hydrogen-rich gas fuel cells. Factors affecting catalytic activity such as support effect, metal size effect, and metal-support interaction are thoroughly discussed. The challenges for practical applications are stated to be achieving acceptable CO outlet concentration, minimizing H2 loss and side reactions, and developing high-performance catalysts resistant to CO2 and steam under realistic conditions. Developing novel catalysts based on the structure-activity relationship is suggested to overcome these challenges.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Raziyeh Jokar, Seyed Mehdi Alavi, Mehran Rezaei, Ehsan Akbari
Summary: The study found that the 10wt% CuO/MnO2 catalyst exhibited the best catalytic performance in CO preferential oxidation reaction, attributed to the synergistic interaction between copper and manganese. However, adding CO2 and/or H2O to the feedstock decreased the catalyst performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Applied
Albano M. Lacoste, Ines S. Tiscornia, Magali Bonne, Laure Michelin, Benedicte Lebeau, Alicia V. Boix
Summary: In this study, SBA-15 and SBA-16 ordered mesoporous silicas were synthesized with different morphologies and copper and cerium oxides were introduced using incipient wetness impregnation and solid-state impregnation methods. The best catalytic performance was achieved with the incipient wetness impregnation method, particularly with the fiber-shaped SBA-15 catalyst. The irregular-shaped SBA-16 catalyst also showed good catalytic activity.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Engineering, Environmental
Ying Du, Fengyu Gao, Yuansong Zhou, Honghong Yi, Xiaolong Tang, Zhiyong Qi
Summary: Carbon monoxide and nitric oxide are widely present in industrial flue gas and pose risks to human health and the environment. The use of CuO-CeO2 composite oxide catalysts shows promising results in the removal of CO and NO, which is important for reducing air pollution. Further research is needed to optimize the performance of these catalysts for industrial applications.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Chemistry, Physical
Shubhadeep Adak, Jabor Rabeah, Ravi Ranjan, Tuhin Suvra Khan, Mukesh Kumar Poddar, Rishi Kumar Gupta, Takehiko Sasaki, Sagar Kumar, Ankur Bordoloi, Chinnakonda S. Gopinath, Angelika Bruckner, Rajaram Bal
Summary: Preferential oxidation of CO in the presence of excess hydrogen is essential for preventing poisoning of the Pt-anode in PEMFCs. A highly active Cu-CeO2 catalyst demonstrated 100% CO conversion at low temperature without deactivation even after 100 hours of operation, making it suitable for practical fuel cell applications. The catalytic mechanism involves reversible changes in valence states of Cu and Ce ions to facilitate CO oxidation to CO2 via oxygen abstraction from the lattice.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Applied
Raul Bruno Machado Silva, Cristine Santos de Oliveira, Erico Teixeira-Neto, Fernando Aparecido Sigoli, Italo Odone Mazali
Summary: In this study, Au/CeO2 materials with CeO2 nanorods were synthesized and their porous structure was optimized through treatment. The treated nanorods showed increased oxygen storage capacity and higher catalytic activity for PROX-CO.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Yang Liu, Aiai Zhang, Lei Xue, Heng Zhang, Yanheng Hao, Yan Wang, Jinfang Wu, Shanghong Zeng
Summary: The nanocage PtCu catalyst exhibits high activity in the preferential oxidation of CO, and shows good resistance to H2O inhibitor.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Lei Xue, Chunjuan Zhang, Jinfang Wu, Qi-Yuan Fan, Yang Liu, Yanxin Wu, Jiaxin Li, Heng Zhang, Fenrong Liu, Shanghong Zeng
Summary: This study focuses on the Cu/CeO2 catalyst for electrocatalytic CO2 reduction, showing that the nanorod Cu/CeO2 catalyst exhibits high selectivity for CO2-to-CH4 conversion with the highest turnover frequency. The catalyst possesses the largest electrochemically active surface area, higher proportion of O-vacancy sites, and better capability of CO2 adsorption and activation, contributing to its high activity. Theoretical calculations reveal that the doping of Cu into CeO2 can significantly lower the reaction energy barrier and change the reaction pathway, improving the catalytic performance for CO2 electroreduction.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Qi Wang, Juhui Gong, Heng Zhang, Qi-Yuan Fan, Lei Xue, Jinfang Wu, Jiaxin Li, Yan Wang, Ze Liu, Rui Gao, Shanghong Zeng
Summary: This study reports a co-promotion strategy of PtCu single-atom alloy and copper-ceria interface for preferential oxidation of CO. The Pt0.1Cu0.19/CeO2 catalyst exhibits superior catalytic performance and excellent stability, attributed to the regulation of the electronic interaction between Pt and Cu as well as the high proportion of oxygen vacancies.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Wenshuai Zhang, Yang Liu, Yajun Dong, Yanheng Hao, Lin Chen, Jiayu Li, Shanghong Zeng, Hong Wang
Summary: In this study, a new nanosphere catalyst with a porous structure is developed, showing improved CH4 selectivity and yield. Experimental and theoretical calculations reveal the role of oxygen vacancies in the CO methanation reaction, further emphasizing the importance of Ceria as a promoter for heterogeneous catalysis.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Chemical
Aiai Zhang, Yang Liu, Jinfang Wu, Lei Xue, Yunong Tang, Xiaolin Yan, Shanghong Zeng
Summary: This study reports the synthesis of xAu-Cu2O/carbon nanotube (CNTs) catalysts and reveals the significant role of interfacial coupling interaction in optimizing oxygen reduction reaction (ORR).
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Chemistry, Physical
Yan Wang, Tong Shi, Qi-Yuan Fan, Yang Liu, Aiai Zhang, Zhaoqiang Li, Yanheng Hao, Lin Chen, Fenrong Liu, Xiaojun Gu, Shanghong Zeng
Summary: In this study, advanced spectroscopic and computational techniques were used to investigate the surface structure and reaction mechanism of tricomponent cerium-tungsten-titanium catalysts. The introduction of graphene oxide improved the dispersion of W and Ce species and resulted in specific bonding structures. The high dispersion of Ce facilitated the generation of oxygen vacancies, enhancing the adsorption and activation of NO and NH3. Experimental and theoretical evidence supported the feasibility of adsorption at low temperatures and revealed the reaction intermediates and interactions. The findings are important for understanding catalyst performance and developing new catalysts.
Article
Engineering, Environmental
Lei Xue, Chunjuan Zhang, Tong Shi, Shangpeng Liu, Heng Zhang, Min Sun, Fenrong Liu, Ying Liu, Yan Wang, Xiaojun Gu, Shanghong Zeng
Summary: In this study, Cu-decorated ZnO nanosheets were prepared and showed impressive electrocatalytic performance in selectively converting CO2 to CO. Through controlling the interfacial chemistry, the angle of reactive sites was reduced, leading to surface modification and electron transfer. Moreover, the Cu decoration alleviated the mass transfer limitation of CO2 and facilitated the formation of key intermediates through a coupling effect.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Aiai Zhang, Yang Liu, Jinfang Wu, Junpeng Zhu, Shuaishuai Cheng, Yan Wang, Yanheng Hao, Shanghong Zeng
Summary: In this study, Cu-deficient Au@Cu2-xS-CNTs electrocatalysts were synthesized and found to exhibit high activity and H2O2 productivity in two-electron ORR. The introduction of Cu defects significantly lowered the reaction energy barrier, enhancing the resistance to H2O generation.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Heng Zhang, Min Sun, Yuansong Zhao, Lei Xue, Yanxin Wu, Yang Liu, Shanghong Zeng
Summary: Polycrystalline Cu catalysts were constructed using capping agents and electrochemical treatment, achieving high Faradaic efficiency (34%) for C2H4 production in electrochemical reduction of carbon dioxide. The obtained CuO pre-catalysts had rough surfaces and abundant grain boundaries. The study also provided evidence for *COOH intermediate formation on the polycrystalline Cu surfaces during CO2 activation.
Article
Chemistry, Physical
Jiaxin Li, Tong Shi, Fuli Tian, Shangpeng Liu, Qiyuan Fan, Yanxin Wu, Min Sun, Heng Zhang, Yanqiu Lei, Fenrong Liu, Shanghong Zeng
Summary: CO2 electroreduction is a promising approach for carbon-based fuel production, but understanding the atomic-level mechanism of catalytic selectivity has been challenging. Using Ag and Cu2O@Ag catalysts as examples, this study shows that the hollow-nanostructured Ag facilitates CO production by lowering the energy barrier of the rate-limiting *CO2 to *COOH step, while the Cu2O-Ag boundaries in the honeycomb-like Cu2O@Ag enhance CO2 physisorption and chemisorption on the catalyst surface. The interfaces of Cu2O@Ag promote CO hydrogenation and CAC coupling, creating alternative reaction pathways towards CH4 and C2H4. This study provides insights for the development of effective electrocatalysts in CO2 electroreduction and beyond.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Junfang Ding, Changjin Xu, Guilan Fan, Tuya Naren, Yan Wang, Yang Liu, Xiaojun Gu, Limin Wu, Shanghong Zeng
Summary: Manipulating the crystal plane-induced CeO2 configurations can improve the dispersion of CuOx and therefore enhance the reactivity of supported catalysts. The optimal catalyst has a nanosphere-shaped CeO2 structure with exposed {111} and {100} facets. Theoretical simulations and experimental results show that the optimal catalyst has highly dispersed CuOx with surface-enriched Cu+ as the active site for catalysis, promoting the carboxyl pathway through lattice oxygen extraction.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Applied
Lei Xue, Qi-Yuan Fan, Yuansong Zhao, Yang Liu, Heng Zhang, Min Sun, Yan Wang, Shanghong Zeng
Summary: By introducing a small quantity of Ag atoms into Cu-based catalysts, electron transfer and surface oxygen defects are improved, enhancing the adsorption and activation of CO2 molecules and effectively reducing the energy barrier for C2H4 formation.
JOURNAL OF ENERGY CHEMISTRY
(2023)
Article
Chemistry, Physical
Aiai Zhang, Yang Liu, Caixia Li, Lei Xue, Ze Liu, Jinfang Wu, Shanghong Zeng
Summary: This study reveals that Ag nanoparticles and carbonizing halloysite nanotubes (CHNTs) can induce the formation of oxygen defects in MnO2, contributing to the generation of active sites. The Ag/MnO2-CHNTs demonstrates superior activity towards ORR with high onset potential, half-wave potential, diffusion-limited current density, long-term durability, and methanol tolerance. Density functional theory calculations show that triggering manganese dioxide defects by introducing Ag nanoparticles and CHNTs can alter the electrocatalytic pathway from a two-electron to a direct four-electron direction for ORR, which enhances ORR activity. Based on the analysis of the results, this finding points out an effective approach for exploring catalysts with improved performance and durability for the ORR reaction.
GREEN ENERGY & ENVIRONMENT
(2023)
Article
Engineering, Environmental
Yang Liu, Tong Shi, Tuya Naren, Yue Jiang, Yan Wang, Fenrong Liu, Shanghong Zeng
Summary: By dispersing CuO and CeO2 on roughened halloysite nanotubes with hydroxyl groups, the effects of binary oxides-support interactions on catalyst stability were investigated and the catalyst durability was improved. Experimental studies, in situ spectroscopic characterizations, and theoretical simulations revealed that etched surfaces created a abundance of reducible species, Cu+ enhanced CO affinity on Cu-Ce-Ox surface and improved selectivity. Strong interactions between oxides and roughened halloysite nanotubes contributed to enhanced catalyst durability. A carboxyl pathway was proposed based on the presence of surface-abundant hydroxyl species. These insights provide guidance for designing stable catalysts with the assistance of supports.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Physical
Yanheng Hao, Yan Wang, Tiantian Zhang, Yang Liu, Qi-Yuan Fan, Yue Jiang, Yonghui Gao, Zhihui Mao, Xiaojun Gu, Shanghong Zeng
Summary: This study demonstrates the fabrication of CuO-Nb2O5/CeO2 catalysts with abundant oxygen vacancies at the interfacial regions, facilitating the redox reaction between Ce3+, Nb5+, and Cu2+ and exhibiting high NH3-SCR activity and N2 selectivity over a wide temperature range. The introduction of proper copper ions induces structure distortion of surface CeO2, improving the incorporation of niobium ions. The embedded Nb synergizes Cu and Ce to generate new adsorptive sites for NOx and NH3, contributing to the NH3-SCR reaction.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
