Zeolite Y and its ultra-stabilized hierarchical derivative (USY) are the most widely used zeolite-based heterogeneous catalysts in oil refining, petrochemisty, and other chemicals manufacturing. After almost 60 years of academic and industrial research, their resilience is unique as no other catalyst displaced them from key processes such as FCC and hydrocracking. The present study highlights the key difference leading to the exceptional catalytic performance of USY versus the parent zeolite Y in a multi-technique study combining advanced spectroscopies (IR and solid-state NMR) and molecular modeling. The results highlight a hitherto unreported proton transfer involving inaccessible active sites in sodalite cages that contributes to the exceptional catalytic performance of USY.

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.202110107DOI Listing

Publication Analysis

Top Keywords

proton transfer
8
exceptional catalytic
8
catalytic performance
8
performance usy
8
unlocking potential
4
potential hidden
4
hidden sites
4
sites faujasite
4
faujasite insights
4
insights proton
4

Similar Publications

The chalcone derivatives with hydroxy group () have been examined using low-temperature fluorescence spectroscopy. The study aimed to freeze the intramolecular charge transfer (ICT) motion in order to reveal the potential hidden transition(s) that are difficult to observe at room temperature. Although chalcone revealed one emission peak at ~667 nm at room temperature, it exhibited two emission peaks (λ = 580 and 636 nm) in EtOH at liquid N temperatures (77 K).

View Article and Find Full Text PDF

A series of colorful binuclear Schiff bases derived from the different diamine bridges including 1,2- ethylenediamine (bis-Et-SA, bis-Et-4-NEt, bis-Et-5-NO, bis-Et-Naph), 1,2-phenylenediamine (bis-Ph-SA, bis-Ph-4-NEt, bis-Ph-5-NO, bis-Ph-Naph), dicyano-1,2-ethenediamine (bis-CN-SA, bis-CN-4-NEt, bis-CN-5-NO, bis-CN-Naph) have been designed and prepared. The optical properties of these binuclear Schiff base ligands were fully determined by UV-Vis absorption spectroscopy, fluorescence emission spectroscopy, and time-dependent-density functional theory (TD-DFT) calculations. The inclusion of D-A systems and/or π-extended systems in these binuclear Schiff base ligands not only enables adjustable RGB light absorption and emission spectra (300~700 nm) but also yields high fluorescence quantum efficiencies of up to 0.

View Article and Find Full Text PDF

Proton-translocating NADH-ubiquinone oxidoreductase (complex I) catalyzes the oxidation of NADH by ubiquinone accompanied by the transmembrane transfer of four protons, thus contributing to the formation of a proton motive force () across the coupling membranes of mitochondria and bacteria, which drives ATP synthesis in oxidative phosphorylation. In recent years, great progress has been achieved in resolving complex I structure by means of X-ray crystallography and high-resolution cryo-electron microscopy, which has led to the formulation of detailed hypotheses concerning the molecular mechanism of coupling of the redox reaction to vectorial proton translocation. To test and probe proposed mechanisms, a comprehensive study of complex I using other methods including molecular dynamics and a variety of biochemical studies such as kinetic and inhibitory analysis is required.

View Article and Find Full Text PDF

Disaccharide trehalose has been proven in many cases to be particularly effective in preserving the functional and structural integrity of biological macromolecules. In this work, we studied its effect on the electron transfer reactions that occur in the chromatophores of the photosynthetic bacterium . In the presence of a high concentration of trehalose, following the activation of the photochemistry by flashes of light, a slowdown of the electrogenic reactions related to the activity of the photosynthetic reaction center and cytochtome (cyt) complexes is observable.

View Article and Find Full Text PDF

Insights into Electrochemical Nitrate Reduction to Nitrogen on Metal Catalysts for Wastewater Treatment.

Environ Sci Technol

January 2025

The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.

Electrocatalytic nitrate reduction reaction (NORR) to harmless nitrogen (N) presents a viable approach for purifying NO-contaminated wastewater, yet most current electrocatalysts predominantly produce ammonium/ammonia (NH/NH) due to challenges in facilitating N-N coupling. This study focuses on identifying metal catalysts that preferentially generate N and elucidating the mechanistic origins of their high selectivity. Our evaluation of 16 commercially available metals reveals that only Pb, Sn, and In demonstrated substantial N selectivity (79.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!