A facile one-step synthesis of polymer supported rhodium nanoparticles in organic medium and their catalytic performance in the dehydrogenation of ammonia-borane

Karahan, Senem
Zahmakıran, Mehmet
Özkar, Saim
A new type of supported rhodium nanoparticles were reproducibly prepared from N(2)H(4)BH(3) reduction of [Rh(mu-Cl)(1,5-cod)](2) without using any solid support and pre-treatment technique. Their characterization shows the formation of well dispersed rhodium(0) nanoparticles within the framework of a polyaminoborane based polymeric support. These new rhodium(0) nanoparticles were found to be the most active supported catalyst in the catalytic dehydrogenation of ammonia-borane in water at room temperature.


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Dogu, G; Ozkan, G; Doğu, Timur (2001-12-15)
A moment technique was developed for the investigation of adsorption on metal surfaces of supported catalysts. The technique was applied to the evaluation of adsorption rate parameters of CO on a Pt-Al2O3 washcoated monolith. The adsorption rate constants evaluated in the temperature range 273-316 K showed significant decrease with an increase in surface coverage. Results of pulse response experiments corresponding to zero coverage gave the apparent activation energy for adsorption as 21 kJ/mol. This method...
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Ayvalı, Tuğçe; Özkar, Saim; Department of Chemistry (2011)
The production of transition metal(0) nanoparticles with controllable size and size distribution are of great importance in catalysis since their catalytic activity decreases as nanoparticles aggregate into clumps and ultimately to the bulk metal. Reducing the particle size of heterogeneous catalyst provides a significant rise in its activity as the fraction of surface atoms increases with decreasing particle size. Therefore, transition metal(0) nanoparticles need to be stabilized to certain extend in their...
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Zahmakiran, Mehmet; Özkar, Saim (2010-05-15)
Zeolite framework stabilized gold(0) nanoclusters were prepared by the ion-exchange/impregnation of Au3+ ions with zeolite-Y followed by reduction of the Au3+ ions using sodium borohydride in aqueous solution, all at 50 degrees C. The zeolite framework stabilized gold(0) nanoclusters were isolated as red powder and characterized by HR-TEM, TEM, TEM-EDX, XRD, XPS, DR-UV-vis, SEM, ICP-OES spectroscopic methods and N-2-adsorption technique. This new material was found to be highly active, selective and reusabl...
An investigation of the interaction of 4-membered rings with adjacent carbanion centers
Guven, OO; Peynircioğlu, Nihad Bekir (2002-01-01)
A series of cyclobutylcarbinyl phenyl ketones was prepared and the rates of base catalyzed hydrogen-deuterium exchange of a-hydrogen atoms were compared with those of appropriate model compounds, to test the validity of an earlier finding, which suggested that a four-membered ring, like the three-membered ring, has the ability to stabilize an adjacent carbanion center. In this study, unlike the cyclopropyl group, no clearly defined stabilization of the adjacent, carbanion center was detected by the 1-phenyl...
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Beker, Levent; Zorlu, Ozge; Külah, Haluk (2014-08-15)
This paper reports a wafer-level attachment method using parylene as an interlayer material for integrating various shaped and fragile substrates into MEMS processes. In the proposed method, the substrates are placed on a handle wafer containing pillars and perforations, and coated with a standard parylene deposition process realized at room temperature, with no applied force. The substrate and the handle wafer are attached to each other via formation of a parylene interlayer. Only poor attachment is observ...
Citation Formats
S. Karahan, M. Zahmakıran, and S. Özkar, “A facile one-step synthesis of polymer supported rhodium nanoparticles in organic medium and their catalytic performance in the dehydrogenation of ammonia-borane,” CHEMICAL COMMUNICATIONS, pp. 1180–1182, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45083.