Platinum shape control

In summary, wc conclude tluu particle shape control in supported metal catalysis is feasible. When a supported platinum catalyst is annealed under conditions where the platinum particles stay dean, the platinum particles assume a spherical shape with flat facets in the (100) and (111) directions. All of the particles in the catalyst assume the same general shape. In contrast, different shapes are observed when the catalyst is annealed in various udgasscs. Shi[ll] showed theoretically that only a few planes can be produced by eciuilibratiug the particles in simple adsorbates. However, w e speculate that one may be able to produce a wide distribution of panicle siiapes. with appropriate adsorbates,... 

Ahmadi TS, Wang ZL, Green TC, Henglein A, El-Sayed MA (1996) Shape-controlled synthesis of colloidal platinum nanoparticles. Science 272 1924... 

Size- and shape-controlled cubo-octahedral platinum(o) nanoparticles of 4nm average size stabilized by sodium polyacrylate showing 111 and 100 surfaces were used to prepare Vulcan supported electrocatalysts. Cyclic voltammetric CO oxidation studies carried out by the thin film rotating disc method show two different sites of CO oxidation (Fig. 2.19). This can be assigned to differences in the activity of the crystal surfaces and is in agreement with single crystal studies. TEM results after cyclic voltammetric characterization show a complete absence of agglomerations. 

Zhenmeng Peng, Hong Yang Designer platinum nanoparticles control of shape, composi-tion in alloy, nanostructure and electrocatalytic property, ""Nano Today , 4, 143-164 (2009). 

Demortiere, A. Launois, P Goubet, N. Albouy, P. A. Petit, C. Shape-controlled platinum nanocubes and their assembly into two-dimensional and three-dimensional superlattices. J. Phys. Chem. B 2008,112, 14583-14592. 

S.-G. (2008) Platinum metal catalysts of high-index surfaces from single-crystal planes to electrochemi-cally shape-controlled nanoparticles. J. Phys. Chem. C, 112, 19801-19817. 

Wang, C., Daimon, H., Onodera, T, Koda, T. Sun, S. A general approach to the size- and shape-controlled synthesis of platinum nanoparticles and their catalytic reduction of oxygen. Angew. Chem. Int Ed. 47... 

Fig. 1.4 Size and shape control of Pt coUoid nanoparticles. Monodispersed platinum nanoparticles 1.7 and 7.2 nm in size (left) with weU-controUed cubic or cuboctahedral shapes (right). Scale bar (left) 5 nm, (center) 50 nm, and (right) 5 nm. The % values (right) refer to the % of nanoparticles with the corresponding shape. (Adapted from ref [28], reprinted with permission)...

Chen JY, Lim B, Lee EP, Xia YN (2009) Shape-controlled synthesis of platinum nanocrystals for catalytic and electrocatalytic applications. Nano Today 4 81-95... 

Sanchez-Sanchez, C. M., J. Solla-Gullon, F. J. Vidal-Iglesias, A. Aldaz, V. Montiel, and E. Herrero. 2010. Imaging structure sensitive catalysis on different shape-controlled platinum nanoparticles. J. Am. Chem. Soc. 132 5622-5624. 

Although various topics relahng to the control of platinum nanostructures have been briefly described in several recent reviews, the discussions have in general been rather generic [2, 6]. As yet, to the best of our knowledge, the shape-control of platinum nanostructures has not been systemahcally reviewed, in part due to the relatively small number of pubhcations in related subjects. Those areas that have been covered well include the catalytic properties of platinum particles [1], while some degree of effort has been appHed to certain aspects of the shape control of Pt nanostructures, such as mulhpods and dendritic nanostructures [21]. 

During the growth of nanocrystals, both thermodynamic and kinetic factors can play important roles in most cases, and either factor may be dominant under certain circumstances. In this section, we discuss the strategies of shape controls of platinum nanocrystals according to the factors in the following two major categories. 

Ahmadi, T.S., Wang, Z.L, Green, T.C., Henglein, A. and ElSayed, M.A. (1995) Shape-controlled synthesis of colloidal platinum nanopartides. Science, 272, 1924. 

Ren, J. and Tilley, R.D. (2007) Shape-controlled growth of platinum nanopartides. Small, 3,1508. 

A simple solution-phase reduction method for the synthesis of shape-controlled platinum nanopartides. Materials Letters, 59,1567. 

Shape control of platinum nanopartides. Advanced Functional Materials, 17, 2219. 

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