Converting Metals into Phosphides: A General Strategy for the Synthesis of Metal Phosphide Nanocrystals
摘要:
Nanocrystals of metal phosphides, which can have useful catalytic, electronic, and magnetic properties, are known to be accessible by using trioctylphosphine (TOP) as a highly reactive phosphorus source. Here we report a general strategy for synthesizing transition metal phosphides, including those with 4d and 5d transition metals that have not previously been reported as unsupported nanocrystals. Unlike previously reported methods that involve direct decomposition of organometallic precursors, our method utilizes preformed metal nanoparticles as templates for generating metal phosphide nanocrystals. Metal nanoparticles are reacted with TOP in a hot solvent (290-360 degrees C) to form transition metal phosphides such as Ni2P, PtP2, Rh2P, PdP2, Pd5P2, and Au2P3. Furthermore, nanostructures such as hollow spheres can be easily made using a Kirkendall-type mechanism, which utilizes metal nanoparticles as reactive templates.
Nature of the modifying action of white phosphorus on the properties of nanosized hydrogenation catalysts based on bis(dibenzylideneacetone)palladium(0)
作者:L. B. Belykh、N. I. Skripov、L. N. Belonogova、V. A. Umanets、T. P. Stepanova、F. K. Schmidt
DOI:10.1134/s002315841105003x
日期:2011.9
the formation of nanosized palladium-based hydrogenation catalysts. The mechanism includes the formation of palladium nanoclusters via the interaction of Pd(dba)2 with the solvent (N,N-dimethylformamide) and substrate and the formation of palladium phosphide nanoparticles. The inhibiting effect exerted by elemental phosphorus on the catalytic process is due to the conversion of part of the Pd(0) into
报道了在基于Pd(dba)2和白磷的体系中形成的纳米颗粒的催化特性和性质。提出了用于形成纳米尺寸的基于钯的氢化催化剂的示意性机理。该机理包括通过Pd(dba)2与溶剂(N,N-二甲基甲酰胺)和底物以及磷化钯纳米粒子的形成。元素磷在催化过程中发挥的抑制作用是由于部分Pd(0)转化为磷化钯(在温和条件下在氢化中不活泼)以及主要分离的钯纳米簇和磷化钯纳米颗粒的形成。通过研究苯中Pd(dba)2和白磷之间的相互作用,可以确定在温和条件下形成钯钯的过程包括以下连续步骤:Pd(0)→PdP 2 →Pd 5 P 2 →Pd 3P.解释了为什么白磷会根据钯前体的性质而对纳米级钯基加氢催化剂的催化性能产生截然相反的影响。
Formation of palladium phosphides in the reaction of bis(dibenzylideneacetone)palladium(0) with white phosphorus
作者:N. I. Skripov、L. B. Belykh、L. N. Belonogova、A. V. Rokhin、T. P. Stepanova、F. K. Shmidt
DOI:10.1134/s1070363212020077
日期:2012.2
of bis(dibenzylideneacetone)palladium(0) with white phosphorus was studied using the methods of NMR, UV spectroscopy, and X-ray powder diffraction. The products of the reaction are shown to be palladium phosphides, their composition depending on the ratio of the reagents. The mechanism of the formation of the palladium-enriched phosphides is suggested, which includes the formation of palladium diphosphide
使用NMR,UV光谱和X射线粉末衍射方法研究了双(二亚苄基丙酮)钯(0)与白磷的反应。反应产物显示为磷化钯,其组成取决于试剂的比例。提出了形成富含钯的磷化物的机理,其包括形成二磷化钯PdP 2,其随后与过量的双(二亚苄基丙酮)钯(0)反应,导致磷化钯Pd 5 P 2,Pd 3 P 0.8,Pd 4.8 P和游离的二亚苄基丙酮。
Effect of the nature of the acido ligand in the precursor on the properties of nanosized palladium-based hydrogenation catalysts modified with elemental phosphorus
作者:N. I. Skripov、L. B. Belykh、L. N. Belonogova、V. A. Umanets、E. N. Ryzhkovich、F. K. Schmidt
DOI:10.1134/s0023158410050137
日期:2010.10
palladium cluster stabilizer—dimethylammonium chloride—in the reaction system via the catalytic hydrolysis of the solvent (DMF). The modifying action of elemental phosphorus on the properties of the palladium catalysts depends on the nature of the acido ligand in the precursor. In the case of oxygen-containing precursors at small P/Pd ratios, elemental phosphorus exerts a promoting effect, raising the TON
Synthesis, properties, and activity of nanosized palladium catalysts modified with elemental phosphorus for hydrogenation
作者:L. B. Belykh、N. I. Skripov、L. N. Belonogova、V. A. Umanets、F. K. Schmidt
DOI:10.1134/s0023158410010088
日期:2010.2
modifier of palladium catalysts for hydrogenation was demonstrated, and the conditions for the synthesis of nanoparticles that are highly efficient in hydrogenation catalysis were optimized. The modifying effect of elemental phosphorus depends on the P/Pd ratio; it is associated with changes in the catalyst dispersity and the nature of the formed nanoparticles containing various palladiumphosphides (PdP2