NiFe catalysts

For hydrogen oxidation bi-component metal doped systems deposited on Raney nickel for AFC Mo and W carbides for AFC prepared by method of precipitation from a gas phase Radicals of following composition -OH, -OSO3H, -COOH, -OPO(OH)3 for PEMFC Some organic catalysts like biologically active [NiFe]-hydrogenase, pyropolymers, etc. ... 

The complexes [Rh(H)(CO)(S4)] and [Ru(H)(PCy3)(S4)] differ from the nickel site in [NiFe] hydrogenases with respect to structure and metal centers, however, they evidently meet several of the principles that must hold true for enzyme centers and competitive catalysts alike. In this case, the complexes... 

Particularly important here is the role of transition metal sulfides. In 1988 Wachtershauser proposed that pyrite, abundant in hydrothermal vent systems, provided an energy source for the first life. He suggested that pyrite provided the catalyst necessary to drive a number of essential chemical reactions which are important precursors to life. More recent studies have confirmed this view and have shown that the sulfides of Fe, Ni, Co, and Zn can play an important role in the fixation of carbon in a prebiotic world (Cody et al., 2004). Transition metal sulfides also play a role in more advance organic synthesis, and Huber and Wachtershauser (1998) showed how amino acids were converted into their peptides using a (NiFe)S catalyst. 

The NiMo catalyst supported on the hollow spherical high surface area CB was compared with the commercial NiMo/Al203 catalyst during the HYD of methyl-naphthalene in an autoclave at 673 K and 9 MPa for 40 min.The CB support ensured very efficient dispersion of metals. The result of this was a markedly higher HYD activity than that of the commercial NiMo/Al203 catalyst. Furthermore, the HYD activity of this NiMo/CB catalyst was compared with Fe/CB, NiFe/CB and FeMo/CB under similar experimental conditions.After 60 min, the conversions were 50, 2, 4 and 7%, respectively. For these experiments, the solution of methyl-naphthalene in tetraline was used as the feed. 

Figure 4 TPR profiles of the oxidic Fe2Fe-T, Fe2Fe-A, NiFe, and CuFe catalysts.

It is well known from classical organometallic chemistry that non-coordinating amine bases affect the behavior of H2 complexes [44]. The azadithiolate motif has been exploited in the design of new catalysts for hydrogen oxidation, as described in the next section on [NiFe] hydrogenases [45]. 

Hydrogenation of carbon monoxide over Si02 supported FeCo, CoNi, NiFe bimetallic catalysts. Appl Catal, 30,... 

M. B. (2011) Systematic evaluation of the dihydrogen-oxidisrng and NAD -reducing soluble [NiFe]-hydrogenase from Ralstonia eutropha H16 as a cofactor regeneration catalyst Biocatal. 

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