The small pore zeolite chabazite (SSZ-13) in the copper exchanged form is a very efficient material for the selective catalytic reduction by ammonia (NH) of nitrogen oxides (NOx) from the exhaust of lean burn engines, typically diesel powered vehicles. The full mechanism occurring during the NH-SCR process is currently debated with outstanding questions including the nature and role of the catalytically active sites. Time-resolved operando spectroscopic techniques have been used to provide new level of insights in to the mechanism of NH-SCR, to show that the origin of stable Cu(I) species under SCR conditions is potentially caused by an interaction between NH and the Cu cations located in eight ring sites of the bulk of the zeolite and is independent of the NH-SCR of NOx occurring at Cu six ring sites within the zeolite.
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http://dx.doi.org/10.1007/s11244-018-0888-3 | DOI Listing |
J Phys Chem Lett
January 2025
International Tomography Center, SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia.
Nuclear magnetic resonance is extremely attractive for operando studies of chemical reactors. However, the heterogeneous catalyst particles placed inside an NMR probe greatly affect the uniformity of the magnetic field. This problem is especially acute when studying heterogeneous hydrogenation processes using parahydrogen.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Department of Physics and Centre for Processable Electronics, Imperial College London, SW7 2AZ, London, United Kingdom.
Conjugated polymers (CPs) with polar side chains can conduct electronic and ionic charges simultaneously, making them promising for bioelectronics, electrocatalysis and energy storage. Recent work showed that adding alkyl spacers between CP backbones and polar side chains improved electronic charge carrier mobility, reduced swelling and enhanced stability, without compromising ion transport. However, how alkyl spacers impact polymer backbone conformation and, subsequently, electronic properties remain unclear.
View Article and Find Full Text PDFAdv Mater
December 2024
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru, 560064, India.
A common challenge in electrochemical processes is developing high performance, stable catalysts for specific chemical reactions. In this work, a Pd-Sn intermetallic compound with Pd site deficiency (PdSn) (x = 0.06) and trace amount of SnO was synthesised by controlled process.
View Article and Find Full Text PDFAnal Chem
December 2024
Paul Scherrer Institut, Center for Energy and Environmental Science, CH-5232 Villigen, Switzerland.
X-ray absorption spectroscopy (XAS) is a powerful technique that provides information about the electronic and local geometric structural properties of newly developed electrocatalysts, especially when it is performed under operating conditions (i.e., ).
View Article and Find Full Text PDFBiochemistry
January 2025
Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8577, Japan.
is a hot spring purple nonsulfur phototrophic bacterium that contains bacteriochlorophyll (BChl) . Here, we present a 2.21 Å cryo-EM structure of the thermostable light-harvesting 1-reaction center (LH1-RC) complex from .
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