scholarly journals Evidence for the Active Phase of Heterogeneous Catalysts through In Situ Reaction Product Imaging and Multiscale Modeling

ACS Catalysis ◽  
2015 ◽  
Vol 5 (8) ◽  
pp. 4514-4518 ◽  
Author(s):  
S. Matera ◽  
S. Blomberg ◽  
M. J. Hoffmann ◽  
J. Zetterberg ◽  
J. Gustafson ◽  
...  
Keyword(s):  
Multiscale Modeling ◽  
Heterogeneous Catalysts ◽  
Active Phase ◽  
In Situ Reaction

scholarly journals In situ reaction monitoring in heterogeneous catalysts by a benchtop NMR spectrometer

2019 ◽  
Vol 56 ◽  
pp. 138-143 ◽  
Author(s):  
Markus Leutzsch ◽  
Andrew J. Sederman ◽  
Lynn F. Gladden ◽  
Michael D. Mantle
Keyword(s):  
Heterogeneous Catalysts ◽  
Reaction Monitoring ◽  
In Situ Reaction

What catalysis needs from the electron microscopist

1988 ◽  
Vol 46 ◽  
pp. 694-695
Author(s):  
Alexis T. Bell
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Surface Composition ◽  
Internal Surface ◽  
Active Phase ◽  
Atomic Scale ◽  
Metal Catalyst ◽  
Internal Surface Area ◽  
Porous Support

Heterogeneous catalysts, used in industry for the production of fuels and chemicals, are microporous solids characterized by a high internal surface area. The catalyticly active sites may occur at the surface of the bulk solid or of small crystallites deposited on a porous support. An example of the former case would be a zeolite, and of the latter, a supported metal catalyst. Since the activity and selectivity of a catalyst are known to be a function of surface composition and structure, it is highly desirable to characterize catalyst surfaces with atomic scale resolution. Where the active phase is dispersed on a support, it is also important to know the dispersion of the deposited phase, as well as its structural and compositional uniformity, the latter characteristics being particularly important in the case of multicomponent catalysts. Knowledge of the pore size and shape is also important, since these can influence the transport of reactants and products through a catalyst and the dynamics of catalyst deactivation.

In-situ reaction between arsenic/selenium and minerals in fly ash at high temperature during blended coal combustion

2020 ◽  
Vol 48 (11) ◽  
pp. 1356-1364
Author(s):  
Jun HAN ◽  
Yang-shuo LIANG ◽  
Bo ZHAO ◽  
Zi-jiang XIONG ◽  
Lin-bo QIN ◽  
...  
Keyword(s):  
High Temperature ◽  
Fly Ash ◽  
Coal Combustion ◽  
In Situ Reaction ◽  
Blended Coal

In-situ/operando techniques to identify active sites for thermochemical conversion of CO2 over heterogeneous catalysts

2021 ◽  
Author(s):  
Kai Feng ◽  
Yaning Wang ◽  
Man Guo ◽  
Jingpeng Zhang ◽  
Zhengwen Li ◽  
...  
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Thermochemical Conversion

scholarly journals Morphology Controlled Synthesis of γ-Al2O3 Nano-Crystallites in Al@Al2O3 Core–Shell Micro-Architectures by Interfacial Hydrothermal Reactions of Al Metal Substrates

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 310
Author(s):  
Dohyeon Han ◽  
Doohwan Lee
Keyword(s):  
Electrostatic Interactions ◽  
Heterogeneous Catalysts ◽  
Metal Substrate ◽  
Inorganic Anions ◽  
Core Shell ◽  
Hydroxyl Groups ◽  
Hydrothermal Reactions ◽  
Fine Control ◽  
Reaction Processes

Fine control of morphology and exposed crystal facets of porous γ-Al2O3 is of significant importance in many application areas such as functional nanomaterials and heterogeneous catalysts. Herein, a morphology controlled in situ synthesis of Al@Al2O3 core–shell architecture consisting of an Al metal core and a porous γ-Al2O3 shell is explored based on interfacial hydrothermal reactions of an Al metal substrate in aqueous solutions of inorganic anions. It was found that the morphology and structure of boehmite (γ-AlOOH) nano-crystallites grown at the Al-metal/solution interface exhibit significant dependence on temperature, type of inorganic anions (Cl−, NO3−, and SO42−), and acid–base environment of the synthesis solution. Different extents of the electrostatic interactions between the protonated hydroxyl groups on (010) and (001) facets of γ-AlOOH and the inorganic anions (Cl−, NO3−, SO42−) appear to result in the preferential growth of γ-AlOOH toward specific crystallographic directions due to the selective capping of the facets by adsorption of the anions. It is hypothesized that the unique Al@Al2O3 core–shell architecture with controlled morphology and exposed crystal-facets of the γ-Al2O3 shell can provide significant intrinsic catalytic properties with enhanced heat and mass transport to heterogeneous catalysts for applications in many thermochemical reaction processes. The direct fabrication of γ-Al2O3 nano-crystallites from Al metal substrate with in-situ modulation of their morphologies and structures into 1D, 2D, and 3D nano-architectures explored in this work is unique and can offer significant opportunities over the conventional methods.

In-situ reaction synthesis Al2O3 overlay modified 7YSZ TBC for NaCl hot corrosion

2021 ◽  
Author(s):  
Jia-Feng Fan ◽  
Guo Liu ◽  
Xue-Shi Zhuo ◽  
Xiao-Feng Zhang ◽  
Jun-Li Feng ◽  
...  
Keyword(s):  
Hot Corrosion ◽  
Reaction Synthesis ◽  
In Situ Reaction

In situ construction of phenanthroline-based cationic radical porous hybrid polymers for metal-free heterogeneous catalysis

2021 ◽  
Vol 9 (12) ◽  
pp. 7556-7565
Author(s):  
Guojian Chen ◽  
Yadong Zhang ◽  
Ke Liu ◽  
Xiaoqing Liu ◽  
Lei Wu ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
Heterogeneous Catalysts ◽  
Hybrid Polymers ◽  
Metal Free ◽  
Oxidation Of Sulfides

Constructing phenanthroline-based cationic radical porous hybrid polymers as versatile metal-free heterogeneous catalysts for both oxidation of sulfides and CO2 conversion.

scholarly journals An In-Situ Reaction Route to Molecular Level Dispersed Bisimide and ZnO Nanorod Hybrids with Efficient Photo-Induced Charge Transfer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Chunzheng Lv ◽  
Lirong He ◽  
Jiahong Tang ◽  
Feng Yang ◽  
Chuhong Zhang
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Self Assembly ◽  
Molecular Level ◽  
Surface Photovoltage ◽  
Zno Nanorod ◽  
In Situ Reaction ◽  
Perylene Bisimide ◽  
Induced Charge

AbstractAs an important photoconductive hybrid material, perylene/ZnO has attracted tremendous attention for photovoltaic-related applications, but generally faces a great challenge to design molecular level dispersed perylenes/ZnO nanohybrids due to easy phase separation between perylenes and ZnO nanocrystals. In this work, we reported an in-situ reaction method to prepare molecular level dispersed H-aggregates of perylene bisimide/ZnO nanorod hybrids. Surface photovoltage and electric field-induced surface photovoltage spectrum show that the photovoltage intensities of nanorod hybrids increased dramatically for 100 times compared with that of pristine perylene bisimide. The enhancement of photovoltage intensities resulting from two aspects: (1) the photo-generated electrons transfer from perylene bisimide to ZnO nanorod due to the electric field formed on the interface of perylene bisimide/ZnO; (2) the H-aggregates of perylene bisimide in ZnO nanorod composites, which is beneficial for photo-generated charge separation and transportation. The introduction of ordered self-assembly thiol-functionalized perylene-3,4,9,10-tetracarboxylic diimide (T-PTCDI)/ ZnO nanorod composites induces a significant improvement in incident photo-to-electron conversion efficiency. This work provides a novel mentality to boost photo-induced charge transfer efficiency, which brings new inspiration for the preparation of the highly efficient solar cell.

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