Carbon dioxide hydrogenation to aromatic hydrocarbons by using an iron/iron oxide nanocatalyst

• Hongwang Wang,
• Jim Hodgson,
• Tej B. Shrestha,
• Prem S. Thapa,
• David Moore,
• Xiaorong Wu,
• Myles Ikenberry,
• Deryl L. Troyer,
• Donghai Wang,
• Keith L. Hohn and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2014, 5, 760–769, doi:10.3762/bjnano.5.88

• catalysts by preventing sintering of active particles during the reaction [23][24]. When using zeolites as solid supports, the product distribution was highly dependent on the structure and acidity of the zeolites [25][26][27]. Iron–zeolite composites were reported as dual functional catalysts, which

Zeolites as nanoporous, gas-sensitive materials for in situ monitoring of DeNO_x-SCR

• Thomas Simons and
• Ulrich Simon

Beilstein J. Nanotechnol. 2012, 3, 667–673, doi:10.3762/bjnano.3.76

• sensor at the same time. By means of temperature-dependent impedance spectroscopy we found that the thermally induced NH3 desorption in H-form and in Fe-loaded zeolite H-ZSM-5 follow the same process, while a remarkable difference under DeNOx-SCR reaction conditions was found. The Fe-loaded catalyst

• elementary catalytic process promoting a full description of the NH3-SCR reaction system. Keywords: DeNOx-SCR; gas sensing; in situ; impedance spectroscopy; zeolite; Introduction Zeolites are crystalline, nanoporous aluminosilicates composed of [TO4] tetrahedra (T = Si, Al). In H-form zeolites protons

• compensate the negative charge of the [AlO4] tetrahedra by forming bridging Si–OH–Al groups, so-called Brønstedt sites, leading to various technical applications in catalysis owing to the resulting acidic properties [1]. The acidity depends on the Si/Al ratio, called the silica modulus of a zeolite, and it

Synthesis and catalytic applications of combined zeolitic/mesoporous materials

• Jarian Vernimmen,
• Vera Meynen and
• Pegie Cool

Beilstein J. Nanotechnol. 2011, 2, 785–801, doi:10.3762/bjnano.2.87

• ” hierarchical mesoporous zeolite, meaning a mesoporous material with zeolitic walls, wherein the micro- and mesopores are interconnected in order to form a hierarchical structure. Such mesoporous zeolites are expected to be superior materials since they will be able to catalyze the typical reactions in which

• pores is vital to maximize the benefit of hierarchy in catalyzed reactions. J. Pérez-Ramírez et al. [48] discussed the different degrees of hierarchy that can be obtained in a combined zeolitic/mesoporous material (Figure 1). In Figure 1a, the reference zeolite system is depicted, which gives rise to

• to TS-1 zeolite. In the hydroxylation of 2,3,6-trimethylphenol, MTS-9 is more active than both Ti-MCM-41 and TS-1. However, there are also examples of combined zeolitic/mesoporous materials, wherein there is no significant improvement when a comparison is drawn with standard zeolites or mesoporous

Generation and agglomeration behaviour of size-selected sub-nm iron clusters as catalysts for the growth of carbon nanotubes

• Ravi Joshi,
• Benjamin Waldschmidt,
• Jörg Engstler,
• Rolf Schäfer and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2011, 2, 734–739, doi:10.3762/bjnano.2.80

• , this allows us to tackle the lower size limit of catalyst particles necessary for CNT growth. The smallest CNT diameter realized so far is 0.4 nm, which was found to be stable only in a template environment, either of a double walled CNT [4][5], or the interior of a porous zeolite AlPO4-5 single

On the reticular construction concept of covalent organic frameworks

• Binit Lukose,
• Agnieszka Kuc,
• Johannes Frenzel and
• Thomas Heine

Beilstein J. Nanotechnol. 2010, 1, 60–70, doi:10.3762/bjnano.1.8

• , and that the synthesis can be carried out solvothermally. MOFs are commercially available, and the scale up of production is continuing. Since the discovery of MOFs, many other crystalline frameworks have been synthesized using reticular chemistry, such as Metal-Organic Polyhedra (MOP) [5], Zeolite