01888nas a2200241 4500008004100000022001400041245012100055210006900176260000900245300001600254490000600270520107700276653002201353653002601375653001801401653002101419653000801440100001801448700001701466700002201483700001801505856012301523 2020 eng d a2168-048500aCO2 hydrogenation to formate by palladium nanoparticles supported on N-incorporated periodic mesoporous organosilica0 aCO2 hydrogenation to formate by palladium nanoparticles supporte cOCT  a14765-147740 v83 a

Development of a heterogeneous catalyst capable of selective transformation of CO2 to valuable products still remains a challenge. In this article, we account for the surfactant-directed synthesis of a new framework-incorporated nitrogen-containing periodic mesoporous organosilica nanosphere (NPMO). A thoroughly characterized N-incorporated hybrid PMO was utilized as a platform for stabilizing well-dispersed and easily accessible Pd nanoparticles (Pd-NPMO) without using any stabilizing agents or expensive dendrimers. Further, this bifunctional hybrid catalyst has been demonstrated to heterogeneously catalyze aqueous phase CO2 hydrogenation (CO2/H-2 ratio 1:3) for the direct synthesis of formate under 4 MPa pressure and at 100 degrees C. To validate the superior performance of the Pd-NPMO catalyst, we compared the activity with Pd-SBA-15 catalysts, and the results showed a 10-fold increase in turnover frequency of 108 h(-1) using Pd on NPMO which envisaged the crucial role of nitrogen sites in this catalyst to boost the CO2 valorization to formate.

10aCO2 hydrogenation10aFormic acid synthesis10aHybrid silica10aPd nanoparticles10aPMO1 aBetsy, K., J.1 aLazar, Anish1 aPavithran, Anjuna1 aVinod, C., P. uhttps://library.ncl.res.in/content/co2-hydrogenation-formate-palladium-nanoparticles-supported-n-incorporated-periodic01971nas a2200253 4500008004100000022001400041245017400055210006900229260000800298300001100306490000700317520104800324653002201372653002101394653002001415653002001435653002501455100001801480700002101498700002101519700002701540700001801567856013201585 2020 eng d a2352-940700aEngineering pore morphology using silica template route over mesoporous cobalt oxide and its implications in atmospheric pressure carbon dioxide hydrogenation to olefins0 aEngineering pore morphology using silica template route over mes cJUN a1005860 v193 a

Highly ordered mesoporous cobalt oxides (denoted as m-Co-KIT-6 and m-Co-SBA-15) with three dimensional and two dimensional pore morphology respectively have been synthesized using 3D KIT-6, and 2D SBA-15 as silica template via nanocasting route. CO2 hydrogenation activity was evaluated for these mesoporous materials under atmospheric pressure conditions. In comparison to nanoparticles of cobalt oxide (Co3O4-nano), mesoporous catalysts showed excellent activity for CO2 hydrogenation due to their higher number of exposed active sites and lower mass diffusion limitations. The ordered mesoporous structure of Co3O4 catalysts favored the chain growth of carbon atoms for the production of C2+ hydrocarbons while Co3O4 nanoparticles showed strong selectivity toward CH4. High selectivity for C2+ (similar to 25%) was obtained for both m-Co-KIT-6 and m-Co-SBA-15 catalysts at 320 degrees C. In addition, the 3D pore structure of m-Co-KIT-6 catalyst exclusively formed more olefins (54.9%) fraction. (C) 2020 Published by Elsevier Ltd.

10aCO2 hydrogenation10aMesoporous CO3O410aOlefin fraction10aPore morphology10aSilica hard template1 aGupta, Sharad1 aCiotonea, Carmen1 aRoyer, Sebastien1 aDacquin, Jean-Philippe1 aVinod, C., P. uhttps://library.ncl.res.in/content/engineering-pore-morphology-using-silica-template-route-over-mesoporous-cobalt-oxide-and-its02185nas a2200229 4500008004100000022001400041245014400055210006900199260000800268300001100276490000800287520137900295653002201674653003501696653001301731653001201744100002101756700001801777700001701795700001801812856012501830 2020 eng d a2468-823100aVariations in activity of Ru/TiO(2 )and Ru/Al2O3 catalysts for CO2 hydrogenation: an investigation by in-situ infrared spectroscopy studies0 aVariations in activity of RuTiO2 and RuAl2O3 catalysts for CO2 h cFEB a1107000 v4823 a

CO2 hydrogenation to methane, an important reaction strategically and also for value adding to CO2, is investigated on two different catalysts, Ru supported on alumina as well as titania to understand better low temperature activity of Ru/TiO2 catalyst. In-situ infrared studies are carried out in three different steps, viz., (i) CO2 adsorption on fully reduced catalyst (ii) reaction of these adsorbed species with gaseous H-2 and (iii) under co-feed of CO2 and H-2, at different temperatures. On Ru/Al2O3 catalyst, CO2 reacts with hydroxyls on the support surface to form carbonate and adsorbs reductively on metal as CO. Further reduction to formate and methyl species occurs on reaction with H. Small concentration of the reactive intermediate formyl forms only at high temperatures. Whereas, bare TiO2 itself seems capable of reductive adsorption of CO2 as formate indicating enhanced reducibility of titania based catalyst. Formyl groups are observed at low temperatures in Ru/TiO2 in step (ii), which further forms methyl and gaseous methane at much lower temperatures when compared to alumina catalyst. Highly reactive CO species loosely bound to metal-support interface observed at high temperatures, which is not present on Ru/Al2O3 catalyst also makes this catalyst superior. In comparison, linearly bound CO seen in alumina catalyst is not as reactive.

10aCO2 hydrogenation10aIn-situ infra red spectroscopy10aRu/Al2O310aRu/TiO21 aDongapure, Pavan1 aBagchi, Sayan1 aMayadevi, S.1 aDevi, Nandini uhttps://library.ncl.res.in/content/variations-activity-rutio2-and-rual2o3-catalysts-co2-hydrogenation-investigation-situ01588nas a2200229 4500008004100000022001400041245016600055210006900221260000800290300001100298490000800309520073100317653002201048653003001070653003801100653002101138653002001159100001701179700001801196700001801214856012601232 2021 eng d a2468-823100aRole of metal-support interaction for atmospheric pressure CO2 hydrogenation over Pd/(Ti)-SBA-15 catalyst: effect of titanium composition on products selectivity0 aRole of metalsupport interaction for atmospheric pressure CO2 hy cJUL a1117320 v5113 aThe potential role of metal-support interaction for tuning the product selectivity during atmospheric pressure CO2 hydrogenation has been demonstrated on Pd/(Ti)-SBA-15 catalyst. Highly dispersed Pd NPs on SBA-15 (Pd/ SBA-15) was synthesized and further modified with titanium of varying composition. Comparison of catalytic activity of Pd/Ti-SBA-15 with its counterparts (Pd/SBA-15 and Pd/TiO2) illustrated the significance of strong PdTi interface in this catalyst and its role in tuning the product selectivity of CO2 hydrogenation. The generation of an ample amount of oxygen vacancies in the Pd/Ti-SBA-15 catalyst with maximum metallic Pd sites in close vicinity of Ti is proposed to boost the CO2 hydrogenation activity.10aCO2 hydrogenation10aMetal-support interaction10aModified deposition precipitation10aoxygen vacancies10aTitanosilicates1 aSoni, Yogita1 aGupta, Sharad1 aVinod, C., P. uhttps://library.ncl.res.in/content/role-metal-support-interaction-atmospheric-pressure-co2-hydrogenation-over-pdti-sba-1501865nas a2200193 4500008004100000022001400041245010100055210006900156260000900225490000800234520121600242653002201458653000801480653001001488653001001498100002001508700001801528856012501546 2024 eng d a2468-823100aExploring the catalytic potential of Mg-Cu alloys for enhanced activity toward CO2 hydrogenation0 aExploring the catalytic potential of MgCu alloys for enhanced ac cMAR 0 v5563 a

CO2, a well-known greenhouse gas, is a potential raw material that can produce various chemicals. Dissociation of CO2 to CO or hydrogenation to formate (HCOO*) or carboxyl (COOH*) intermediate is crucial in determining the reaction pathway for CO2 conversion. In this work, we demonstrate that alloys of Mg-Cu exhibit greater activity toward activation and hydrogenation of CO2 than transition metal alloys reported so far. Two different compositions of Mg-Cu, namely Mg2Cu and MgCu2, have been studied using periodic Density Functional Theory (DFT). Our investigations reveal that CO2 chemisorbs on both intermetallic alloys. Coadsorption of CO2 with H2O leads to the spontaneous formation of COOH* over Mg2Cu(224), whereas a negligible barrier (0.04 eV) is observed for MgCu2(311). HCOO* formation has a barrier of 0.34 eV and 0.42 eV on Mg2Cu(224) and MgCu2(311), respectively. Dissociation of CO2 to CO is kinetically unfavourable on both compositions of Mg-Cu. We provide a rationale for the observed activity by analyzing the electronic structure. Notably, the spontaneous hydrogenation of CO2 makes earth -abundant metals suitable candidates for alloying that await experimental verification.

10aCO2 hydrogenation10aDFT10aMg2Cu10aMgCu21 aThakkar, Kavita1 aJoshi, Kavita uhttps://library.ncl.res.in/content/exploring-catalytic-potential-mg-cu-alloys-enhanced-activity-toward-co2-hydrogenation02302nas a2200229 4500008004100000022001400041245012500055210006900180260000800249490000700257520147900264653001901743653002201762653002001784653003601804653002301840100001701863700002601880700002401906700001701930856012501947 2024 eng d a1439-423500aSize and morphology dependent activity of Cu clusters for CO2 activation and reduction: a first principles investigation0 aSize and morphology dependent activity of Cu clusters for CO2 ac cDEC0 v253 a

Various Cu-based materials in diverse forms have been investigated as efficient catalysts for electrochemical reduction of CO2; however, they suffer from issues such as higher over potential and poor selectivity. The activity and selectivity of CO2 electro reduction have been shown to change significantly when the surface morphology (steps, kinks, and edges) of these catalysts is altered. In light of this, size and morphology dependent activity of selected copper clusters, Cun (n=2-20) have been evaluated for the activation and reduction of CO2 molecule. The phase-space of these copper clusters is rich in conformations of distinct morphologies starting from planar, 2D geometries to prolate-shaped geometries and also high-symmetry structures. The binding efficiency and the activation of CO2 are highest for medium sized clusters (n=9-17) with prolate-morphologies as compared to small or larger sized CunCO(2) clusters that are existing mainly as planar (triangular, tetragonal etc.) or highly-symmetric geometries (icosahedron, capped-icosahedron etc.), respectively. The best performing (prolate-shaped) CunCO2 conformations are quite fluxional and also they are thermally stable, as demonstrated by the molecular dynamics simulations. Furthermore, on these CunCO(2) conformations, the step-by-step hydrogenation pathways of CO2 to produce value-added products like methanol, formic acid, and methane are exceptionally favorable and energy-efficient.

10aCO2 activation10aCO2 hydrogenation10aCopper clusters10aDensity Functional Theory (DFT)10amolecular dynamics1 aAmin, Seerat1 aKrishnamurty, Sailaja1 aDar, Manzoor, Ahmad1 aJoshi, Krati uhttps://library.ncl.res.in/content/size-and-morphology-dependent-activity-cu-clusters-co2-activation-and-reduction-first02307nas a2200337 4500008004100000022001400041245015300055210006900208260000900277300001100286490000800297520117300305653002001478653002401498653002201522653000901544653002301553653001201576653002501588653004301613100002401656700001801680700001901698700002001717700002501737700001701762700001801779700002501797700001801822856012901840 2025 eng d a1385-894700aExploring the electronic modulation in controlling the activity and selectivity of Ni-Au-In based catalyst in atmospheric pressure CO2 hydrogenation0 aExploring the electronic modulation in controlling the activity  cSEP  a1659210 v5203 a

Nickel-based catalysts are widely used for the hydrogenation of CO2 but encounter stability challenges during prolonged reactions and at elevated temperatures. At atmospheric pressure, nickel primarily promotes methane formation in CO2 hydrogenation reactions. In this work, we demonstrate that the stability and activity of nickel can be significantly enhanced through gold (Au) modification. Furthermore, we achieve a near-complete selectivity switch from methane to CO by incorporating indium (In), mediated through the formation of Au-In alloy. This catalyst exhibits excellent CO2 conversion and CO selectivity at relatively lower temperatures (400 degrees C), addressing a major bottleneck in the Reverse Water-Gas Shifts (RWGS) reaction. XPS studies demonstrate an interesting electron transfer mechanism facilitated by gold, which involves the formation of electronrich Au species (Au delta-) and the development of Au-In alloys. This process improves the reducibility of nickel oxide while allowing a fraction of nickel to remain in its metallic form, managing a facile hydrogenation process and regulating the shift in selectivity from CH4 to CO.

10aAlloy formation10aBimetallic catalyst10aCO2 hydrogenation10aRWGS10aSelectivity switch10asynergy10aTrimetallic catalyst10aXPS (X-ray photoelectron spectroscopy)1 aBajpai, Jyotsna, P.1 aGupta, Sharad1 aGoud, Devender1 aDeka, Diku, Raj1 aJagtap, Anuradha, V.1 aKumar, Pawan1 aAhamed, Momin1 aPeter, Sebastian, C.1 aVinod, C., P. uhttps://library.ncl.res.in/content/exploring-electronic-modulation-controlling-activity-and-selectivity-ni-au-based-catalyst