Since the discovery of the Ullmann reaction over a century ago, in 1901, [1] the transition-metal-catalyzed cross-coupling reaction has played an important role in the synthesis of CÀC bonds. [2] In 1981, Suzuki discovered a novel Pd-catalyzed crosscoupling reaction of aryl boronic acids and aryl halides, [3] which has been applied widely [4][5][6][7][8][9][10][11] and for which he received the 2010 Nobel prize in chemistry. This reaction has become an extremely powerful process for the synthesis of biaryls, which have a diverse spectrum of applications, ranging from pharmaceuticals to materials science. [12][13][14][15] Recently, the use of nanocatalysts has increased rapidly and has resulted in the development of several active and efficient nano-catalysts for various protocols. [16][17][18][19][20] These systems have several advantages over conventional catalysts, such as superior activity and improved stability. Combining metal nanoparticles with a support of choice provides a large field for the discovery of new, highly active nanocatalysts for important and challenging reactions, which also offer the additional advantage of recyclability. The preparation of Pd nanoparticles is usually based on the reduction of a metal salt in the presence of a reducing agent and a stabilizer. Many substrates, such as polymers, [21] dendrimers, [22] ionic liquids, [23] ordered mesoporous silica, [24] and carbon nanotubes, [25] have been used as stabilizers and supports for Pd nanoparticles. We recently reviewed these nano-catalysts for Suzuki coupling reactions [26] and observed that an extensive range of nano-catalyst systems was developed for this process in a short period of time. Although most of these nanocatalyst systems are active and usable, two main challenges still remain unresolved: 1) stable nano-catalysts that avoid activity loss from particle-size growth during the reaction caused by Ostwald ripening and 2) active nano-catalysts that use challenging, but economical chloroarenes as substrates.In a continuation of our search for green and sustainable nano-catalytic protocols, [27][28][29][30][31][32][33][34] we herein report novel Pd-nanocatalysts supported on our recently discovered high-surfacearea silica exhibiting a unique fibrous morphology (KCC-1). [27,28] We discovered that the high surface area of KCC-1 is attributable to fibers and not pores, which dramatically increases its accessibility.[27] We believe that this unique property will be very useful for the design of silica-supported catalysts, for which the accessibility of active sites can be increased significantly. After demonstrating the validity of this concept for the hydro-metathesis of olefins by using a KCC-1/TaH catalyst system, [28] we designed highly disperse Pd-nanoparticles supported on fibers of KCC-1 to examine the advantages of fibrous KCC-1 as a catalyst support in Suzuki coupling reactions.The first step in accomplishing this catalyst design was the functionalization of KCC-1 with amino groups, which could then act as pseudo chelators...

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A monodispersed 15 nm Ni 9 Pt 1 catalyst synthesized via a reverse microemulsion method, shows a lower activation energy than both Ni and Pt catalysts during the methane cracking reaction. Thanks to the synergic effect of Ni-Pt alloy, this catalyst presents a stable H 2 formation rate at 700 C, and forms carbon nanotubes, anchoring the catalyst particles on top.Although supported nickel-based catalysts are mostly studied to show good methane cracking reactivity, 1 the formation of low levels of CO by the interaction of cracked surface "carbon" with the "oxygen" from supported catalysts is unavoidable. 2,3

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