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The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface‐induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA‐15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched‐row structure in softer Pt nanoparticles, which was identified by microscopic and surface‐sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt−CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS. [ABSTRACT FROM AUTHOR]

The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface‐induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA‐15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched‐row structure in softer Pt nanoparticles, which was identified by microscopic and surface‐sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt−CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS. [ABSTRACT FROM AUTHOR]

András Sápi et al. have reported on a nanodesigned Pt/MnOx interface that enhances the activity of the reverse water gas shift (RWGS) reaction. The interface generates edge dislocations, which destabilize and release linearly adsorbed CO from the Pt nanoparticle, resulting in improved catalytic performance. In addition, other research articles in the journal cover topics such as biosensors, cyclooligomers, photochemistry, and singlet fission. [Extracted from the article]

András Sápi et al. have reported on a nanodesigned Pt/MnOx interface that enhances the activity of the reverse water gas shift (RWGS) reaction. The interface generates edge dislocations, which destabilize and release linearly adsorbed CO from the Pt nanoparticle, resulting in improved catalytic performance. In addition, other articles in the journal discuss topics such as biosensors, cyclooligomers, photochemistry, and singlet fission. The authors of these articles explore various scientific advancements and their applications. [Extracted from the article]

[Display omitted] • PtNPs enhance CO 2 methanation activity in mesoporous and commercial Co 3 O 4 differently. • Partial coverage of Co-Pt alloy particles by the Co x O y layer has been postulated. • New basic centres are responsible for the higher enhancement effect of the Pt/c-Co 3 O 4. Based on our previous investigations, it turned out that the Co 3 O 4 material is a promising catalyst in the ambient pressure CO 2 methanation. This work aims at understanding the Pt-Cobalt-Oxide surface interaction and its effect on the catalytic performance. The incorporation of Pt nanoparticles into the mesoporous Co 3 O 4 (Pt/m-Co 3 O 4) and commercial Co 3 O 4 (Pt/c-Co 3 O 4) improves the catalytic activity of both catalysts by a factor of ∼ 1.4 and ∼ 1.9 respectively at 673 K. The same tendency towards the increased basicity was also observed. Morphology-induced surface basicity was previously shown to play a key role in determining the catalytic activity of free-standing supports. From HR-TEM (-EDX), EXAFS, CO 2 -TPD, and CO chemisorption measurements it was established that during the pre-treatment, Co-Pt alloy particles partially covered by the Co x O y layer are formed. It has been postulated that this structure transformation generates new basic centres, the amount of which per unit surface area is significantly larger for Pt/c-Co 3 O 4 and this in turn is responsible for the higher enhancement effect of the Pt/c-Co 3 O 4 catalyst in the CO 2 methanation. This study emphasizes the importance of the surface structure exploration for the dynamic catalytic systems in order to reach maximum activity and selectivity in the CO 2 methanation. [ABSTRACT FROM AUTHOR]

This work investigates the effect of the Potassium promoter and the calcination temperature on the catalytic activity in the dry reforming of methane reaction and compares the performance of the Ni, Co, Fe–Al2O3 trimetallic catalysts with the reference Ni–Al2O3. Although higher activity was achieved with the Ni–Al2O3, trimetallic catalysts resulted in a more favorable CO/H2 ratio and considerably better coke resistance. Higher calcination temperature led to the increase in coke formation which caused the sintering of the catalysts. Promoting samples with 0.5%K in order to improve the coke formation resistance, reduced the catalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mixed Na-Fe 3 O 4 and Fe 5 C 2 can enhance the performance of CO 2 hydrogenation to C 5+. • An optimal oxide/carbide ratio is crucial for achieving high yields of C 2 -C 4 olefins and C 5+ hydrocarbons. • Closer proximity of oxide and carbide hindered CH 4 formation and olefin hydrogenation. • Oxide/carbide reduction can enhance carbon shell graphitization and C 5+ formation. CO 2 hydrogenation into sustainable chemical feedstocks and fuels is a pivotal focus of energy research. Fe-based catalysts have emerged as promising candidates due to their high efficiency in the CO 2 hydrogenation toward C 2 –C 4 olefins and C 5+ hydrocarbons. Fe 5 C 2 is known as the active phase of the CO 2 hydrogenation. Therefore, it is imperative to discern the roles of active phases in product distribution. Accordingly, in the present study, Fe 5 C 2 is synthesized separately and physically mixed with Na-Fe 3 O 4. The effects of oxide/carbide ratio, the proximity of active phases, and reduction treatment are investigated. The results show that adding carbide to oxide in an appropriate ratio significantly increases CO 2 conversion due to the controlled reduction of the oxide phase and enhanced CO 2 adsorption. Additionally, a closer distance (mixed-powder pellets) between Na-Fe 3 O 4 and Fe 5 C 2 results in higher selectivity for C 2 -C 4 olefins and C 5+ hydrocarbons and less CH 4. Furthermore, the graphitized layers of reduced catalyst (R-Na-Fe 3 O 4 /Fe 5 C 2 (70/30 wt%)) enhance the selectivity to C 2 -C 4 olefins (40 %) and C 5+ hydrocarbons (35 %) at around 40 % CO 2 conversion. In contrast, amorphous carbon in the non-reduced catalyst (NR-Na-Fe 3 O 4 /Fe 5 C 2 (70/30 wt%)) favors more C 2 -C 4 paraffins and CH 4. Therefore, the interplay between the influential factors, i.e., oxide/carbide ratio, spatial distance, and reduction treatment, can result in tailoring an efficient CO 2 hydrogenation catalyst toward the formation of valuable hydrocarbons. [ABSTRACT FROM AUTHOR]

[Display omitted] • <2 nm Pt, Ru and Rh NCs were anchored over CeO 2 /MCF17. • Supported metal NCs exhibited excellent catalytic performance for CO 2 reduction. • Ru NCs/CeO 2 exhibited ∼ 99% selectivity to CH 4. • Effect of two entirely different supports (CeO 2 and MCF 17) was evaluated. Efficient conversion of CO 2 into CH 4 and CO brings an important opportunity to get valuable feedstock for a variety of industrially important reactions as both CH 4 and CO are widely used as starting materials for the synthesis of valuable fuels and chemicals. Herein, we synthesized sub-nanometer (<2nm) Platinum (Pt), Ruthenium (Ru) and Rhodium (Rh) nanoclusters (NCs) via colloidal method; successfully decorated over mesoporous CeO 2 and high surface area (HSA) siliceous meso -cellular foam (MCF 17) and tested for high-pressure CO 2 reduction at lower temperature range (220–340 °C). Pt and Ru NCs exhibited typical reverse water gas shift (RWGS) and methanation catalytic performance respectively with minimal influence of the nature of support however, Rh NCs showed drastic variations in the product selectivity which exhibited strong influence of the support over the product distribution. Furthermore, Ru NCs (with a relatively lower metal loading ∼ 1 wt%) were found to be highly selective to CH 4 (∼99 %) and stable (upto 40 hr time on stream) with either CeO 2 /MCF 17 at 340 °C; also Ru NCs exhibited comparatively the highest CO 2 conversion (∼93 % in case of Ru NCs/CeO 2) among the supported metal NCs. HRTEM results showed that metal NCs were homogeneously dispersed with a controlled and uniform particle size (<2nm); no substantial agglomeration of Ru NCs were observed after reaction. Beside the stable dispersion of NCs, Near Ambient Pressure (NAP) in situ XPS of Ru/CeO 2 showed that the dynamic Ce3+/Ce4+ ratio of CeO 2 can attribute to the high activity and selectivity. [ABSTRACT FROM AUTHOR]

Constructing stable and effective bio-synthesized heterostructure-photocatalyst has been demanding in the advancement of the photocatalysis-field. Herein, bismuth vanadate (BiVO 4) was bio-fabricated using Curcuma longa via hydrolysis route for effective charge separation due to supramolecular-organic-semiconductor system of C. longa. Transmission Electron Microscopy (TEM), High Resolution-Transmission Electron Microscopy (HR-TEM), Surface Assisted Electron Diffraction (SAED), and Electron Impedance Spectroscopy (EIS) reflected successful fabrication of heterojunction between C. longa and BiVO 4. The as-fabricated nanoflowers of C. longa/ BiVO 4 (BVO-G) reflected highly efficient photocatalytic fragmentation of Organochlorine Pesticides (OCPs) [2,4-D (2,4-dichlorophenoxy acetic acid, 90.2%) and 2,4-DP [2-(2,4-dichlorophenoxy propionic acid, 70.52%)] on comparison with pristine BiVO 4 [2,4-D (45.94%) and 2,4-DP (28.18%)] within 120 min of visible-light-irradiation and also showed much better efficiency in comparison with earlier fabricated materials. Further, optical studies including photochemical responses and radical-quenching showed that h+, ·O 2 − and ·OH were responsible for the fragmentation of these recalcitrant herbicides. Based on in-situ High Performance Liquid Chromatography (HPLC) and Liquid Chromatography Mass Spectroscopy (LCMS) analysis, degradation pathways were designed. This work provides an in depth understanding of bio-fabrication of photocatalyst by enhancing the active sites of the reactants and hindering the recombination of photogenerated charge carriers. [Display omitted] • Bismuth vanadate nanoparticles (BVO-G) were bio-fabricated using C. longa. • Heterojunction reduces charge transfer resistance. • Visible-LED source was irradiated for photocatalytic degradation. • 100% MO dye, 90% 2,4-D, and 69.5% 2,4-DP was degraded using BVO-G. • LCMS reflected 90% TOC removal in 2,4-D using BVO-G. [ABSTRACT FROM AUTHOR]