We employ a combination of Z-contrast scanning transmission electron microscopy (ZSTEM) and first-principles density-functional calculations to investigate the interaction between metal atoms and cubic alumina catalytic supports. We show that there are two observed La sites at the porous γalumina surface, and that single La atoms do not exhibit a tendency to cluster. Cr behaves very differently...

The rationalisation of the influence of acidity and pore size of several solid oxides so that they selectively act as supports for preparation of encapsulated porphyrin hybrid materials or as catalysts for synthesis of porphyrins in solution is discussed. Encapsulated porphyrin yields are dependent on both the acidity and the material pore size, Al-MCM-41 being the best fitting solid, with Lewi...

First-principles calculations were performed to investigate the effect of Pd concentration and oxygen vacancies on the stability of Pd at LaFeO3 surfaces. We found a much stronger tendency of Pd to segregate by taking the aggregation of Pd at LaFe1-xPdxO3-y surfaces into consideration, resulting in a pair of Pd-Pd around a vacancy. Moreover, we predicted that one oxygen-vacancy-containing FeO2-...

In this report, vulcan XC-72 supported PtNi alloy catalyst nanoparticles were synthesized by electroless deposition method using NaBH4 as a reduction agent. The properties of the synthesized Pt-Ni/C catalysts were investigated and evaluated. Transmission electron microscopy (TEM) results showed that PtNi alloy catalysts dispersed well on the carbon supports and their particle size was in the ra...

Finally, HDN C-N cleavage normally results in the formation of N-H and C-H bonds.4 Analysis of the gas phase above the CoMo reactions in which Et2" was observed revealed only hydrogen. The ethyl groups lost are observed by GC-mass spectroscopy as Et2NBu and EtOH. The mechanism of transformation of two ethyl groups to a butyl group or one ethyl group to ethanol is not apparent; however, in the r...

A facile method is developed for the large-scale growth of hierarchical transition-metal (Cu, Fe, and Ni) vanadate nanosheets on corresponding metal mesh as supports. The hierarchical transition-metal vanadate nanosheets were in situ grown on the metal meshes through an orientational etching process and simultaneous nucleation and growth process. Interestingly, the morphologies of the vanadate ...

The hydroformylation of alkenes is a major commercial process used for the production of oxygenated organic compounds. Commercial hydroformylation processes may produce significant quantities of waste material. When the hydroformylation reaction is performed using a homogeneous catalyst, an organic or aqueous solvent is employed and a significant effort must be expended to recover the catalyst ...

mcm-41 is one of the groups of mesoporous materials that have wide applications as adsorbents, ion exchangers and catalyst supports. in this work spherical and rod-like mcm-41s were synthesized in homogeneous and heterogeneous reaction media, respectively. for synthesis of these materials the cationic surfactant cetyltrimethylammonium bromide (ctmabr) was used as template and tetraethylorthosil...

Introduction Bulk gold is a chemically inert metal, and had previously been disregarded as a candidate for catalytic applications [1]. Haruta’s pioneering work [2] showed exceptional reactivity on gold nanoparticles of 2-5 nm in diameter. Among reactions, the low temperature CO oxidation [3] on Au has created a strong interest. Model catalyst samples, which consist of planar metal oxide surface...