Selective oxidation of methane to methanol by dioxygen (O2) is an appealing route for upgrading abundant resource and represents one the most challenging reactions in chemistry due overwhelmingly higher reactivity product (methanol) versus reactant (methane). Here, we report that gold nanoparticles dispersed on mordenite efficiently catalyze selective molecular oxygen aqueous medium presence carbon monoxide. The productivity reaches 1300 μmol gcat-1 h-1 or 280 mmol gAu-1 with 75% selectivity...

Processes that rely on heterogeneous catalysts underpin the production of bulk chemicals and fuels. In spite this, understanding interplay between structure reactivity these complex materials remains elusive—rendering rational improvement existing systems challenging. Herein, we describe efforts to understand capable selective thermochemical conversion CO2 methanol using a surface organometallic chemistry (SOMC) approach. particular, focus remarkable, but often subtle, roles metal–metal...

The optimization of the air–solid contactor is critical to improve efficiency direct air capture (DAC) process. To enable comparison contactors and therefore a step toward optimization, two are prepared in form pellets wash-coated honeycomb monoliths. desired amine functionalities successfully incorporated onto these industrially relevant by means procedure developed for powders, providing materials with CO2 uptake not influenced morphology structure according sorption measurements....

Simple, commercially available borane adducts, H3B·THF and H3B·SMe2, have been used to catalyse the hydroboration of alkynes alkenes with pinacolborane give alkenyl alkyl boronic esters, respectively. Alkynes terminal underwent highly regioselective linear ester products. Good functional group tolerance was observed for substrates bearing ester, amine, ether halide substituents. This catalytic process shows comparable reactivity transition-metal-catalysed protocols.

The direct conversion of CO2 to CH3OH represents an appealing strategy for the mitigation anthropogenic emissions. Here, we report that small, narrowly distributed alloyed PdGa nanoparticles, prepared via surface organometallic chemistry from silica-supported GaIII isolated sites, selectively catalyze hydrogenation CH3OH. At 230 °C and 25 bar, high activity (22.3 molMeOH molPd-1 h-1) selectivity CH3OH/DME (81%) are observed, while corresponding Pd nanoparticles show low selectivity. X-ray...

The development of an efficient heterogeneous catalyst for storing H2 into CO2 and releasing it from the produced formic acid, when needed, is a crucial target overcoming some intrinsic criticalities green hydrogen exploitation, such as high flammability, low density, handling. Herein, we report both reactions prepared by immobilizing molecular iridium organometallic onto high-surface mesoporous silica, through sol–gel methodology. presence tailored single-metal catalytic sites, derived...

The direct synthesis of methanol via the hydrogenation CO2, if performed efficiently and selectively, is potentially a powerful technology for CO2 mitigation. Here, we develop an active selective Cu-Zn/SiO2 catalyst by introducing copper zinc onto dehydroxylated silica surface organometallic chemistry atomic layer deposition, respectively. At 230 °C 25 bar, optimized shows intrinsic formation rate 4.3 g h-1 gCu-1 selectivity to 83%, with space-time yield 0.073 gcat-1 at contact time 0.06 s...

Au-Zn catalysts have previously been shown to promote the hydrogenation of CO2 methanol, but their active state is poorly understood. Here, silica-supported bimetallic alloys, prepared by surface organometallic chemistry (SOMC), are be proficient for methanol. In situ X-ray absorption spectroscopy (XAS), in conjunction with gas-switching experiments, used amplify subtle changes occurring at this tailored catalyst during reaction. Consequently, an alloy identified and undergo subsequent...

Molecular-level understanding of the acid/base properties heterogeneous catalysts requires development selective spectroscopic probes to establish structure-activity relationships. In this work we show that substituting surface protons in oxide supports by isolobal N-heterocyclic carbene (NHC) Ag cations and measuring their

Hydrogenation of CO2 to methanol is foreseen as a key step close the carbon cycle. In this study, we show that introducing Ga into silica-supported nanoparticles based on group 8-9 transition noble metals (M = Ru, Os, Rh, and Ir - MGa@SiO2) switches their reactivity from producing mostly methane (sel. > 97%) (>50% CH3OH/DME sel.) alongside CO only byproduct. These catalysts, prepared via surface organometallic chemistry (SOMC) approach, consist small, alloyed, narrowly distributed MGa...

The direct conversion of syngas to ethanol is a promising route for the sustainable production value-added chemicals and fuels. While Fe-promoted Rh-based catalysts have long been studied because their notable activity selectivity towards ethanol, nature Rh-Fe interaction catalyst structure under reaction conditions remain poorly understood due intrinsic complexity heterogeneous prepared by conventional approaches. In this work, we construct well-defined RhFe@SiO2 model via surface...

Transition-metal hydrides (TMHs) find numerous applications across fields, from catalysis to H2 storage. Yet, determining the structure of TMHs can remain a challenge, as hydrogen is difficult detect by X-ray based or classical spectroscopic techniques. Considering that deuterium isotope (D) quadrupolar nucleus (I = 1) and coupling constant (CQ) depends on distance between D its bonding partner E (dED), we evaluate this trend molecularly-defined transition-metal deuterides (TMDs) through...

The direct conversion of syngas to ethanol is a promising route for the sustainable production value-added chemicals and fuels. While Fe-promoted Rh-based catalysts have long been studied because their notable activity selectivity towards ethanol, nature Rh-Fe interaction catalyst structure under reaction conditions remain poorly understood due complexity heterogeneous prepared by conventional approaches. In this work, we construct well-defined RhFe@SiO2 model via surface organometallic...

Organic materials that conduct both electrons and ions are integral to implantable bioelectronics because of their conformable nature. There is a dearth these highly sensitive cations, which the majority on surface neurons. This manuscript offers solution using an extended ribbon structure defect-free, providing high electronic mobility along its fused backbone, while edge ribbons promotes ionic conductivity. We incorporated mixed ion/electron conductors into neural probes implanted them in...

A series of rare earth complexes the form Ln(L^R)₃ supported by bidentate <italic>ortho</italic>-aryloxide–NHC ligands are reported (L^R = O(<italic>o</italic>-C₆H₂–^tBu₂-2,6-CN(C₂H₂)NR); R ⁱPr, ^tBu, Mes; Ln Ce, Sm, Eu).

The influence of the phase ZrO2 support (monoclinic, tetragonal, and amorphous, referred to as m-, t-, am-, respectively) on nature surface species involved in methanol synthesis rates their formation ZrO2-supported, In-based catalysts for CO2 hydrogenation has been investigated. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) at 300 °C 20 bar (H2:CO2:N2 = 3:1:1 volume ratio) m-ZrO2:In, In2O3/t-ZrO2, In2O3/am-ZrO2 (m-ZrO2:In is a solid solution) shows that...

The synthesis of well-defined materials as model systems for catalysis and related fields is an important pillar in the understanding catalytic processes at a molecular level. Various approaches employing organometallic precursors have been developed established to make monodispersed supported nanoparticles, nanocrystals, films. Using rational design principles, new family based on group 10 metals suitable generation small nanoparticles metal oxides has developed. Particle formation SiO2...

Carbon dioxide is a major contributor to global climate change and ocean acidification, making efficient capture utilization required step for sustainable development. A pivotal aspect of development close the carbon cycle by converting CO2 with “green” H2 value-added product or fuel, such as methanol. In this context, supported metal catalysts have been extensively investigated, focusing on role promoters and/or supports drive catalytic performance. particular, besides classical like zinc,...

The selective hydrogenation of CO2 to CH3OH is a crucial part efforts mitigate climate change via the methanol economy. Understanding nature and role active sites essential for designing highly catalysts. Here, we examine Cu nanoparticles dispersed on TiO2 Ti-containing SiO2 supports, where Ti moieties these materials are reducible different extents, using surface organometallic chemistry approach, together with state-of-the-art characterization methods (UV–vis, infrared (IR), electron...

Rh-based catalysts modified by transition metals have been intensively studied for CO2 hydrogenation due to their high activity. However, understanding the role of promoters at molecular level remains challenging ill-defined structure heterogeneous catalysts. Here, we constructed well-defined RhMn@SiO2 and Rh@SiO2 model via surface organometallic chemistry combined with thermolytic precursor (SOMC/TMP) approach rationalize promotional effect Mn in hydrogenation. We show that addition shifts...

A combination of ab initio molecular dynamics/metadynamics and in situ spectroscopy reveal the structural response mono- bimetallic nanoparticles to adsorbates under various conditions relevant hydrogenation carbon dioxide.

Olefin metathesis has been established as an efficient tool to build carbon-carbon bonds, and its widespread applications in organic synthesis have made possible by the development of homogeneous catalysts – Grubbs Schrock-type that operate through same intermediates Chauvin mechanism. With d0 catalysts, first elementary step, olefin-coordination, is often rate determining, but it rarely explored due lack accessible relevant molecular analogs. Here, we develop a surrogate this key...

The development of efficient catalysts for the hydrogenation CO2 to methanol is foreseen as a key step close carbon cycle and enable sustainable development. In this study, we show that introducing Ga into silica-supported nanoparticles based on group 8-9 noble transition metals (M = Ru, Os, Rh, Ir – MGa@SiO2), switches their reactivity from producing purely CH4 (selectivity &gt;97%) (50% CH3OH/DME) alongside CO only byproduct. These catalysts, prepared via surface organometallic chemistry...

Since its emergence over 50 years ago, the structure of surface sites in Ziegler–Natta catalysts, which are responsible for a major fraction world's supply polyethylene (PE) and polypropylene (PP), has remained elusive. This is part due to complexity these systems that involve multiple synthetic steps components, namely, MgCl2 support, transition-metal chloride, several organic modifiers, known as donors, used prior some instances during activation step with alkyl aluminum. Due favorable...