Preparation of hierarchical dandelion-like CuO microspheres with enhanced catalytic performance for dimethyldichlorosilane synthesis

Gold catalysts have been studied in-depth due to their unique activities for catalytic CO oxidation. Supports have intrinsic motivation for the high activity of gold catalysts. Thermally stable urchin-like CuO microspheres, which are potential support for gold catalysts, were prepared by facile solution-method. Then gold nanoparticles were loaded on them by deposition-precipitation method. The obtained gold catalysts were characterized by SEM, XRD, TEM, BET, ICP, and XPS. Their catalytic activity for CO oxidation was also evaluated. TEM results revealed that the gold nanoparticles with small sizes were highly distributed on the CuO surface in Au1.0/CuO-300. XPS observations demonstrated that the gold species in Au1.0/CuO-300 was of metallic state. Among the as-prepared catalysts, the Au1.0/CuO-300 catalyst displayed the best performance for CO oxidation and achieved 100% CO oxidation at 80 °C. It kept 100% conversion for 20 h at a reaction temperature of 180 °C, and showed good reusability after three reaction-cycles. The possible catalytic mechanism of Au1.0/CuO-300 catalyst for CO oxidation was also briefly proposed.

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The design and catalytic performance of molybdenum active sites on an MCM-41 framework for the aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

Catalysis Science & Technology ◽

10.1039/c8cy02291g ◽

2019 ◽

Vol 9 (3) ◽

pp. 811-821 ◽

Cited By ~ 7

Author(s):

Zhao-Meng Wang ◽

Li-Juan Liu ◽

Bo Xiang ◽

Yue Wang ◽

Ya-Jing Lyu ◽

...

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Aerobic Oxidation ◽

Catalytic Performance ◽

Mcm 41

The catalytic activity decreases as –(SiO)3Mo(OH)(O) > –(SiO)2Mo(O)2 > –(O)4–MoO.

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Optimizing electron density of nickel sulfide electrocatalysts through sulfur vacancy engineering for alkaline hydrogen evolution

Journal of Materials Chemistry A ◽

10.1039/d0ta05594h ◽

2020 ◽

Vol 8 (35) ◽

pp. 18207-18214

Author(s):

Dongbo Jia ◽

Lili Han ◽

Ying Li ◽

Wenjun He ◽

Caichi Liu ◽

...

Keyword(s):

Hydrogen Evolution ◽

Electron Density ◽

Rational Design ◽

Nickel Sulfide ◽

Catalytic Performance ◽

Sulfide Catalysts ◽

Sulfur Vacancy

A novel, rational design for porous S-vacancy nickel sulfide catalysts with remarkable catalytic performance for alkaline HER.

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Catalytic Resonance Theory: Parallel Reaction Pathway Control

10.26434/chemrxiv.10271090 ◽

2019 ◽

Author(s):

M. Alexander Ardagh ◽

Manish Shetty ◽

Anatoliy Kuznetsov ◽

Qi Zhang ◽

Phillip Christopher ◽

...

Keyword(s):

Chemical Reactions ◽

Active Site ◽

Active Sites ◽

Reaction Pathway ◽

Control Strategies ◽

Oscillation Amplitude ◽

Catalytic Performance ◽

Parallel Reaction ◽

Resonance Theory ◽

Static Conditions

Catalytic enhancement of chemical reactions via heterogeneous materials occurs through stabilization of transition states at designed active sites, but dramatically greater rate acceleration on that same active site is achieved when the surface intermediates oscillate in binding energy. The applied oscillation amplitude and frequency can accelerate reactions orders of magnitude above the catalytic rates of static systems, provided the active site dynamics are tuned to the natural frequencies of the surface chemistry. In this work, differences in the characteristics of parallel reactions are exploited via selective application of active site dynamics (0 < ΔU < 1.0 eV amplitude, 10<sup>-6</sup> < f < 10<sup>4</sup> Hz frequency) to control the extent of competing reactions occurring on the shared catalytic surface. Simulation of multiple parallel reaction systems with broad range of variation in chemical parameters revealed that parallel chemistries are highly tunable in selectivity between either pure product, even when specific products are not selectively produced under static conditions. Two mechanisms leading to dynamic selectivity control were identified: (i) surface thermodynamic control of one product species under strong binding conditions, or (ii) catalytic resonance of the kinetics of one reaction over the other. These dynamic parallel pathway control strategies applied to a host of chemical conditions indicate significant potential for improving the catalytic performance of many important industrial chemical reactions beyond their existing static performance.

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