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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]

Catalysts with magnetic properties can be easily recovered from the reaction medium without loss by using a magnetic field, which highly improves their applicability. To design such systems, we have successfully combined the magnetic properties of nickel ferrite nanoparticles with the positive properties of carbon-based catalyst supports. Amine-functionalized NiFe2O4 nanoparticles were deposited on the surfaces of nitrogen-doped bamboo-like carbon nanotubes (N-BCNT) and carbon nanolayers (CNL) by using a coprecipitation process. The magnetizable catalyst supports were decorated by Pd nanoparticles, and their catalytic activity was tested through the hydrogenation of nitrobenzene (NB). By using the prepared catalysts, high nitrobenzene conversion (100% for 120 min at 333 K) and a high aniline yield (99%) were achieved. The Pd/NiFe2O4-CNL catalyst was remarkable in terms of stability during the reuse tests due to the strong interaction formed between the catalytically active metal and its support (the activity was retained during four cycles of 120 min at 333 K). Furthermore, despite the long-lasting mechanical stress, no significant palladium loss (only 0.08 wt%) was detected. [ABSTRACT FROM AUTHOR]

A nitrogen doped carbon aerogel was used as a substrate for the atomic layer deposition of TiO2 and ZnO layers in various thicknesses. The bare and composite products were analyzed using Raman spectroscopy, XRD, N2 adsorption, SEM-EDX, TEM, XPS, and ICP-OES and their photocatalytic activity was investigated in decomposing methyl orange dye under UV light irradiation. We investigated the effect of the different metal oxides and their thickness dependence on the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Nitrogen‐doped, bamboo‐like carbon nanotubes (BCNTs) were synthesized from butylamine by catalytic chemical vapor deposition (CCVD method). The nanotubes were oxidized by H2SO4/HNO3 treatment and used to prepare calcium alginate gelled BCNT spheres. These beads were first carbonized and then Pd, Rh and Ni nanoparticles were anchored on the surface of the spheres. These systems were then applied as catalysts in CO2 hydrogenation. The BCNT support was examined by Raman spectroscopy, dynamic light scattering (DLS) and X‐ray photoelectron spectroscopy (XPS). The prepared catalysts were characterized by HRTEM and SEM. The oxidation pretreatment of BCNTs was successful, with the electrokinetic potential of the water‐based dispersion of BCNTs measuring −59.9 mV, meaning the nanotube dispersion is stable. Pyridinic and graphitic types of incorporated nitrogen centers were identified in the structure of the nanotubes, according to the XPS measurements. The Pd‐containing BCNT sphere catalyst was the most efficient in the catalytic studies. The highest conversion was reached on the Pd catalyst at 723 K, as well as at 873 K. The difference in the formation rate of CO was much less at 873 K between the Pd and Rh compared to the 723 K values. Accordingly, the application of Pd‐containing BCNT/carbon‐supported catalyst favored the generation of CO. However, the Ni‐BCNT/carbon catalyst leads to the formation of CH4 as the major product. Simply the best: Nitrogen‐doped, bamboo‐like carbon nanotubes (BCNTs) were synthesized from butylamine by catalytic chemical vapor deposition. The nanotubes were used to prepare calcium alginate gelled BCNT spheres which were subsequently carbonized and loaded with Pd, Rh and Ni nanoparticles. These systems were used as catalysts in CO2 hydrogenation, with the Pd derivative found to demonstrate the highest conversion at 723 and 873 K. [ABSTRACT FROM AUTHOR]

The effect of illumination on the adsorption and reaction of ethane was investigated on TiO 2 and TiO 2 -supported Pt metals. IR studies showed that new absorption bands developed as a result of illumination of the catalysts. The photocatalytic decomposition of ethane was very limited on pure TiO 2 : the conversion was only ∼4% at 300 K in 210 min. Deposition of Pt metals onto TiO 2 markedly enhanced the rate of photo-induced decomposition of C 2 H 6 . Highest conversion of C 2 H 6 , 23.5%, was measured over Pt/TiO 2 and the turnover frequency was also the highest on this catalyst. Addition of CO 2 to ethane exerted no influence on the photocatalysis of ethane. Surprisingly, the main gaseous product of the photocatalytic reaction is H 2 with a small amount of CH 4 . Ethylene was not detected even in traces, indicating the complete degradation of C 2 H 6 to H 2 and carbon containing deposit. Temperature programmed reduction (TPR) revealed that the carbonaceous deposit on the catalysts is very stable. On Rh/TiO 2 it reacted with H 2 to give CH 4 (Tp = 453 and 604 K), C 2 H 6 and C 3 H 8 (Tp = 602 K). Similar values were found on Pt/TiO 2 . The promoting effect of metals was explained by a better separation of charge carriers induced by illumination and by the enhanced electronic interaction between metals and TiO 2 . [ABSTRACT FROM AUTHOR]