Article
Chemistry, Physical
Matthias Stehle, Abhijeet Gaur, Sebastian Weber, Thomas L. Sheppard, Michael Thomann, Achim Fischer, J-D Grunwaldt
Summary: In this study, two Bi-Mo-Co-Fe-O catalysts were synthesized and tested for their catalytic performance in selective oxidation of propylene to acrolein. The structural changes during oxidation and reaction processes were observed using various operando techniques. The formation of different oxide phases and the interaction between MoO3 and other oxides were found to be crucial for high performance. The combination of complementary operando methods bridged the knowledge gap between simplified model systems and complex catalysts.
JOURNAL OF CATALYSIS
(2022)
Review
Chemistry, Physical
Francisco Zaera
Summary: Catalysis in industrial chemical processes has long been studied through various spectroscopic techniques like vibrational and X-ray spectroscopies, allowing for a molecular-level understanding of catalytic mechanisms. These techniques help researchers explore the intricate details of catalytic processes and advancements in the field.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Linda Klag, Abhijeet Gaur, Matthias Stehle, Sebastian Weber, Thomas L. Sheppard, Jan-Dierk Grunwaldt
Summary: This study systematically investigated the activity and selectivity of Bi-Mo-Co-Fe oxide catalysts in selective oxidation of isobutene. The results showed that the activity and selectivity of the catalysts depend on the variety and interaction of metal oxide phases, and the reducibility of Fe3+ is crucial for catalytic activity.
Article
Energy & Fuels
Michael Hoeber, Philipp Wachter, Benjamin Koenigshofer, Felix Muetter, Hartmuth Schroettner, Christoph Hochenauer, Vanja Subotic
Summary: More than 75% of today's H-2 production is based on reforming processes using heterogeneous catalysts. However, there is no established direct online monitoring method for commercial Ni-based catalysts. This study demonstrates the use of electrochemical impedance spectroscopy for online monitoring of Ni catalysts and examines the impact of different contacting methods on measurement results.
Review
Chemistry, Multidisciplinary
Katrin Koehnke, Niklas Wessel, Jesus Esteban, Jing Jin, Andreas J. Vorholt, Walter Leitner
Summary: Observing and understanding the reaction mechanisms and catalyst deactivation in molecular catalysis is a challenging task in green chemistry. Operando experimental setups, which rely on spectroscopic analysis and chromatographic techniques, have the potential to elucidate these mechanisms. This review covers different spectroscopic techniques for monitoring molecular transition metal catalysts in solution and numerical methods to analyze the complex signals. Examples of industrially relevant chemical reactions demonstrate the importance of operando studies in developing stable and selective catalysts for greener processes.
Article
Chemistry, Physical
Thu D. Nguyen, Weiqing Zheng, Fuat E. Celik, George Tsilomelekis
Summary: The study found that incorporating CeO2 into the support changed the interaction patterns between MoOx catalysts and the support, enhanced the reoxidation effect of the oxidant CO2, and promoted the oxidative dehydrogenation pathway of ethane.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Review
Chemistry, Applied
Kai Feng, Yaning Wang, Man Guo, Jingpeng Zhang, Zhengwen Li, Tianyu Deng, Zhihe Zhang, Binhang Yan
Summary: The catalytic conversion of CO2 to fuels or chemicals is an effective way to mitigate the greenhouse effect. In-situ/operando techniques are crucial for identifying active sites and determining reaction mechanisms, as the structure of heterogeneous catalysts usually changes dynamically during reactions. Various optical and X-ray spectroscopy techniques have been applied to monitor the evolution of active site structures in real-time under reaction conditions.
JOURNAL OF ENERGY CHEMISTRY
(2021)
Review
Chemistry, Physical
Wanyi Liao, Shanshan Wang, Yan Zhang
Summary: The key to achieving the breakthrough of hydrogen energy lies in the development and design of efficient electrocatalysts. Heterostructure catalysts with a mass of functional interfaces play a decisive role in enhancing catalyst activity, stability, and reaction kinetics. However, there is still a lack of detailed discussion on the actual reaction processes occurring at the catalytic interface, which hinders the understanding of the true catalytic mechanism. Therefore, relying on advanced in situ/operando characterization techniques to understand the working mechanism of heterostructure catalysts is crucial for rational design of advanced catalysts.
Review
Chemistry, Physical
Han-Wen Cheng, Shan Wang, Guanyu Chen, Zhengwang Liu, Dominic Caracciolo, Merry Madiou, Shiyao Shan, Jincang Zhang, Heyong He, Renchao Che, Chuan-Jian Zhong
Summary: This review emphasizes the latest insights into heterogeneous catalysts under relevant reaction conditions using in situ/operando transmission electron microscopic techniques. By discussing atomic-scale and nanoscale details, it highlights the challenges and opportunities in terms of catalytic properties and design applications.
ADVANCED ENERGY MATERIALS
(2022)
Review
Chemistry, Physical
Wanyi Liao, Shanshan Wang, Yan Zhang
Summary: This article discusses the application of heterostructure catalysts in water electrolysis, emphasizing the importance of in situ characterization techniques in understanding interface reconstruction, reaction mechanisms, and component roles. The current challenges and prospects in the design of heterostructure electrocatalysts are also discussed in detail.
Review
Chemistry, Inorganic & Nuclear
Hilke Petersen, Claudia Weidenthaler
Summary: This review discusses the up-to-date in situ/operando methods for the comprehensive characterization of nanoporous materials, highlighting the growing variety of nanoporous materials and their potential applications. The evolution from ex situ examination to complex in situ or operando methods allows for establishing structure-property relationships and optimizing nanoporous materials for specific processes. Recent developments on both established and emerging methods are discussed for future applications.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Review
Chemistry, Physical
Ali M. Abdel-Mageed, Shilong Chen, Corinna Fauth, Thomas Haering, Joachim Bansmann
Summary: The study investigates the fundamental characteristics and complex structure-reactivity relationship of highly active Au/CeO2 catalysts in CO oxidation using various techniques, including operando X-ray absorption spectroscopy, in situ diffuse reflectance FTIR, and Raman spectroscopy. The results highlight the complex relationship among the oxidation state, size of the Au nanoparticles, the redox properties of CeO2 support, and the dynamics of O-2 activation.
Article
Chemistry, Physical
Jeongjin Kim, Hanseul Choi, Daeho Kim, Jeong Young Park
Summary: The strong metal-support interaction (SMSI) phenomenon at metal-oxide interfaces plays a crucial role in enhancing catalytic performance, although the mechanistic explanation of SMSI remains a long-standing issue. Through operando characterization tools, active sites at metal-oxide interfaces can be identified under working conditions, providing mechanistic insights into the geometric and electronic functions during catalytic reactions.
Article
Chemistry, Multidisciplinary
Justus S. Diercks, Juan Herranz, Kathrin Ebner, Natasa Diklic, Maximilian Georgi, Piyush Chauhan, Adam H. Clark, Maarten Nachtegaal, Alexander Eychmueller, Thomas J. Schmidt
Summary: In recent years, operando/in situ X-ray absorption spectroscopy (XAS) has become an important tool in the electrocatalysis community. This study investigates the impact of catalyst layer (CL) thickness on Pd-hydride formation trends in carbon-supported Pd nanoparticles and an unsupported Pd aerogel. The results suggest the need for minimizing CL thickness in spectro-electrochemical experiments and using complementary thin-film control measurements.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Inorganic & Nuclear
Zhenzhu Xu, Zibin Liang, Wenhan Guo, Ruqiang Zou
Summary: Electrochemical energy conversion through electrocatalysis offers promising solutions to global energy crisis and environmental issues. Understanding the mechanism and structure-activity relationship of key electrocatalytic processes is crucial for designing efficient electrocatalysts. Vibrational spectroscopic methods, such as Raman and FTIR-based techniques, are powerful tools for monitoring surface transformations and reaction intermediates in electrocatalytic processes, attracting attention for future research in this field.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Chemistry, Physical
Fei Wang, Changming Li, Xiaoyu Zhang, Min Wei, David G. Evans, Xue Duan
JOURNAL OF CATALYSIS
(2015)
Article
Chemistry, Multidisciplinary
Fei Wang, Shan He, Hao Chen, Bin Wang, Lirong Zheng, Min Wei, David G. Evans, Xue Duan
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2016)
Review
Chemistry, Physical
Fei Wang, Min Wei, David G. Evans, Xue Duan
JOURNAL OF MATERIALS CHEMISTRY A
(2016)
Article
Chemistry, Multidisciplinary
Fei Wang, Shitong Zhang, Changming Li, Jie Liu, Shan He, Yufei Zhao, Hong Yan, Min Wei, David G. Evans, Xue Duan
Article
Chemistry, Physical
Jiaojiao Zhao, Yurong He, Fei Wang, Wentao Zheng, Chunfang Huo, Xi Liu, Haijun Jiao, Yong Yang, Yongwang Li, Xiaodong Wen
Article
Chemistry, Physical
Dan Luo, Yurong He, Xin Yu, Fei Wang, Jiaojiao Zhao, Wentao Zheng, Haijun Jiao, Yong Yang, Yongwang Li, Xiaodong Wen
Summary: The type of active metal is the key factor determining the selectivity of primary amine, impacting the competitive hydrogenation reactions between primary imine and secondary imine.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Jiaojiao Zhao, Yurong He, Fei Wang, Yusen Yang, Wentao Zheng, Chunfang Huo, Haijun Jiao, Yong Yang, Yongwang Li, Xiaodong Wen
Summary: Metal leaching is a significant obstacle for CO-containing heterogeneous catalysis systems, with the modulation of the metal surface impacting structural stability under a CO atmosphere. The CoGa IMC/SiO2 catalyst exhibits notably less cobalt leaching in hydroformylation reaction compared to Co/SiO2, and is capable of generating aldehydes without forming Co carbonyl species. Despite weaker metal interaction strength, the Co-Ga bond in bulk phase shows higher structural stability than Co-Co bond with CO molecule adsorption.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Applied
Mengjiao Xing, Ling Zhang, Jian Cao, Yuanlong Han, Fei Wang, Kun Hao, Lihua Huang, Zhichao Tao, Xiaodong Wen, Yong Yang, Yongwang Li
Summary: The impact of Al species state and concentration on the content of Al pairs in the preparation of ZSM-5 zeolite was studied. The state of the Al species was found to be an important factor in determining the content of Al pairs in ZSM-5 zeolites.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Jian Cao, Mengjiao Xing, Yuanlong Han, Kun Hao, Ling Zhang, Fei Wang, Wentao Zheng, Zhichao Tao, Xiaodong Wen, Yong Yang, Yongwang Li
Summary: In this study, alkali treatment and phosphorus modification were used to improve the catalytic stability and hydrothermal stability of ZSM-5 catalysts. The introduction of mesopores enhanced the dispersion of phosphorus species and improved the stability of the aromatization reaction. The sample treated with an appropriate concentration of alkali had the highest aromatic selectivity.
Article
Chemistry, Physical
Huanjiang Wang, Yuchen Zhang, Dan Luo, He Wang, Yurong He, Fei Wang, Xiaodong Wen
Summary: In addition to the main reaction, understanding the structure-activity relationship in the side reactions is another important goal for catalysis science. In this study, the catalytic activities and selectivities of various active metals were investigated in the reductive amination of furfural (FAL). It was observed that Ru-based catalysts showed higher hydrogenation of furfurylamine (FAM) at a much higher reaction temperature compared to Co-and Ni-based catalysts (130 vs. 50 degrees C), indicating the influence of active metal on the excessive hydrogenation of FAM. The evaluation of FAM hydrogenation further supported the relationship between H2 reaction pressure and catalytic activity.
MOLECULAR CATALYSIS
(2023)
Article
Chemistry, Physical
Yongfang Sun, Huan Ma, Yueyue Jiao, Yunlei Chen, Xiaoze Yuan, Xiangyu Zhang, Fei Wang, Dongdong Xiao, Yi Wang, Dachao Hong, Yuwei Zhou, Lin Gu, Yong Yang, Yongwang Li, Xiao-Dong Wen
Summary: Ternary intermetallic electrides (LaTMSi) are a class of electride materials with unique geometric and electronic structures, showing excellent catalytic performance. The structural stability of LaTMSi in air and water is higher compared to conventional electrides. However, their catalytic activities decrease in the presence of H2O as the product. High-temperature calcination can remove the deactivated surface caused by exposure to H2O, but frequent reactions with H2O and calcination can lead to complete phase transition to oxides. The dissociation of H2O and phase transition are also observed in LaCoSi and LaNiSi ternary intermetallic electrides.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Xiangyu Zhang, Yunlei Chen, Yongfang Sun, Fei Wang, Xiao-Dong Wen, Tian-Nan Ye
Summary: In this study, a simplified and facile preparation method for the [Ca24Al28O64](4+)(e(-))(4) electride material (C12A7:e(-)) was presented. The successful preparation of C12A7:e(-) was confirmed by XRD patterns and magnetic behavior analysis. The concentration of electrons in the prepared C12A7:e(-) powder was calculated to be approximately 2.23 x 10(21) cm(-3), evaluated by iodometry and TPD. DFT calculations provided insight into the unique electronic structure of C12A7:e(-). Additionally, substituting Ca reductant with CaH2 reduced the solid-state reaction temperature from 1100 to 950°C, attributed to thermodynamic effects such as a reduction in &UDelta;G.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Junbo Zhang, Guoqiang Ding, Yueqing Wang, Fei Wang, Hongxing Wang, Yubo Liu, Yulei Zhu, Yongwang Li
Summary: In this study, H-Beta zeolites with different Si/Al ratios were prepared and evaluated for decarburization catalysis to produce furfural. The synergistic catalytic effect between the *BEA channel and framework-Al was found to be crucial. Fructose showed the highest FAL yield, and cellulose also had a relatively high yield.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)