関連する実験動画

Updated: Jan 13, 2026

Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether

Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether

Published on: August 17, 2019

CO酸化におけるPtCe修飾ゼオライトZSM-5の触媒性能の構造駆動チューニング

Marina Shilina¹, Irina Krotova¹, Konstantin Maslakov¹

¹Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia.

Molecules (Basel, Switzerland)

|January 10, 2026

Abstract:

The catalytic oxidation of CO is of great technological importance for the treatment of vehicle and industrial exhaust gases. PtCe-catalysts of low-temperature CO oxidation were prepared by the impregnation of ZSM-5 zeolite (Z) with aqueous solutions of H₂PtCl₆ and Ce(NO₃)₃, varying the order of metal deposition and thermal treatment conditions. The relationships between structure transformations and catalyst performance were established based on the SEM, TEM, EDX, DRIFT, and X-ray photoelectron spectroscopies data. For the Ce/Pt/Z sample, in which cerium was deposited after platinum, the 100% CO conversion temperature was only 120 °C. The inverse deposition sequence of metals (Pt/Ce/Z catalyst) resulted in CO oxidation at a higher temperature that can be decreased to 110 °C by redox treatment. The prepared catalysts were also active in the CO oxidation in excess hydrogen (PROX) but were not selective enough. However, the activity of PtCe-modified ZSM-5 enhanced greatly in the repeated cycles of CO oxidation (TOX) after testing in PROX. It is suggested that enhancing the interaction between Pt and Ce is a key factor in tuning the catalyst performance. The 0.2 wt.% Pt catalysts showed the best performance and provided complete CO conversion at 95 °C, which is a pronounced result for low-loaded Pt catalysts.

キーワード:

一酸化炭素触媒作用セリウム酸化白金ゼオライトZSM-5

さらに関連する動画

Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation

Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation

Published on: July 18, 2017

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications

Published on: July 25, 2025

関連する概念動画

Catalysis

Catalysis

The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.

Turnover Number and Catalytic Efficiency

Turnover Number and Catalytic Efficiency

The turnover number of an enzyme is the maximum number of substrate molecules it can transform per unit time. Turnover numbers for most enzymes range from 1 to 1000 molecules per second. Catalase has the known highest turnover number, capable of converting up to 2.8×106 molecules of hydrogen peroxide into water and oxygen per second. Lysozyme has the lowest known turnover number of half a molecule per second.
Chymotrypsin is a pancreatic enzyme that breaks down proteins during digestion....

Reduction of Alkenes: Catalytic Hydrogenation

Reduction of Alkenes: Catalytic Hydrogenation

Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...

Introduction to Mechanisms of Enzyme Catalysis

Introduction to Mechanisms of Enzyme Catalysis

For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes...

Catalytically Perfect Enzymes

Catalytically Perfect Enzymes

The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.

Most enzymes...

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...