等离子体制备负载型金属纳米催化剂的研究进展

等离子体主要是由离子、电子等粒子组成的呈电中性且高度离子化的气体。可在室温条件下,利用等离子体中的高能粒子对化学物质进行还原,避免高温条件下粒子发生团聚,易得到粒径小、分散性好的纳米颗粒。对近年来等离子体技术制备负载型金属纳米催化剂及其催化性能进行了综述。     

负载金属催化剂的结构性能表征

综述了H2-TPR,TEM,XRD等物化方法在负载型金属催化剂的结构性能（包括金属分散度、表面结构、电子状态）方面的应用,为更好地认识和使用负载型金属催化剂提供了可靠的依据。     

负载型金属催化剂制备新技术研究进展

负载型金属催化剂因为其独特的催化性能在众多领域得到广泛应用。传统的催化剂制备方法有浸渍法,沉淀法,离子交换法和熔融法等。文章综述了溶剂化金属原子浸渍法,超临界技术和微波技术在负载型金属催化剂制备中的应用。     

基于金属有机骨架材料负载型催化剂的研究进展

金属有机骨架材料（MOFs）是由有机配体和金属离子或团簇通过配位键自组装形成的具有分子内孔隙结构的有机-无机杂化材料,近年来在电化学、传感器、生物医学和催化等方面具有广泛的应用。尤其在催化领域,MOFs材料与传统无机材料相比,不仅具有极大的比表面积、高的孔隙率、可调节的孔结构,还包括3个重要的可改性部分：金属配位点、有机配体和纳米空腔。,综述了MOFs材料作为催化材料的特点以及MOFs负载型催化剂构建方式及应用,并对金属有机骨架材料负载型催化剂的瓶颈问题进行了分析,对发展方向进行了展望。     

负载型金属纳米催化剂对催化反应性能影响的研究进展

负载型金属纳米催化剂是由活性金属纳米粒子和载体组成的.金属纳米粒子是各种纳米技术应用中的关键功能部件,因为它们的尺寸、形状和组成具有独特的性质,且具有比表面积大的优点.对于相同质量的金属和纳米金属粒子而言,纳米金属表面积是普通金属表面积的千百倍,这个优点使其吸附作用非常强.纳术金属广泛的被应用于光学器件、电子器件、信息...     

活性炭负载金属催化剂的研究进展

活性炭作为一种优良的催化剂载体被广泛应用于催化领域,其经酸碱预处理或氧化预处理后表面可负载一种或多种金属催化剂,是优化各种金属催化剂性能的有效方法之一。为给今后活性炭载体催化剂的研发提供一些参考和方向,从单一金属催化剂负载和复合金属催化剂负载的制备、催化活性及应用着手,对近年来新制备的活性炭负载金属催化剂进行综述。     

负载型金属催化剂催化4-硝基苯酚加氢研究进展

4-硝基苯酚是一种典型的有机污染物,采用催化加氢的方式将其转化为具有工业价值的4-氨基苯酚,保护环境的同时还可以创造一定的经济价值,具有重要的科学意义.本文简要介绍了近期国内外研究成果,从负载型催化剂的活性组分、载体类型、两个方面归纳总结了负载型催化剂催化4-硝基苯酚加氢反应的研究进展,并对未来的研究趋势进行了展望.     

负载型Pd催化剂

介绍了制备负载型钯催化剂的几种方法,以及它在反应中的应用。阐述了几种催化剂载体的优点,最后对这种催化剂的前提提出展望。     

超临界流体沉积技术制备负载型金属催化剂的研究进展

综述了近年来超临界流体沉积技术在制备负载型金属纳米催化剂方面的应用及研究进展,介绍了近年来学者们利用超临界流体特殊的溶剂化特征、近乎于零的表面张力、高扩散系数、低黏度、易调变等优势,制备负载型金属纳米催化剂的研究成果。主要从超临界流体沉积过程中金属前驱盐的溶解、吸附、还原3个方面分别进行了阐述。集中讨论了对沉积效果影响显著的溶解度、吸附热力学、扩散动力学以及还原方法等问题。此外,还针对目前超临界流体沉积技术在制备金属纳米复合材料中所遇到的提高金属利用率、颗粒尺寸控制、分散性等焦点问题进行了讨论。     

Models of metal catalysts: beyond single crystals

Because solid catalysts are typically complex in structure and composition, researchers have often used structurally simple models in attempts to identify catalytic sites and understand reaction mechanisms. Among models of metal catalysts, single crystals are the prototypes, but, because they cannot represent support effects or the smallest metal clusters and cannot easily be used in long-term catalyst testing, they are complemented by other types of model catalysts, including metal particles on well-defined planar supports and nearly molecular clusters of a few metal atoms each on metal oxide and zeolite supports. This account is a comparison of the various types of model metal catalysts and a summary of the advantages and limitations of each. Examples of rhodium and of platinum catalysts are given to illustrate the catalyst types and connections between them. More data are needed as a basis for comparisons of the performance of the various model catalysts.     

Layered double hydroxides: precursors for multifunctional catalysts

One-pot cascade reactions which involve multifunctional catalysts possessing different functions on the surface attract a growing interest. Relevant examples of the use of this type of catalysts in one-pot syntheses involving hydrogenation/dehydrogenation and aldol condensation reactions which give rise to valuable organic compounds are reported in this paper. It is shown that the layered double hydroxides (LDH) are precursors materials particularly adapted for the preparation of catalysts exhibiting acido/basic and redox sites. The paramount importance of the nature (Lewis or Bronsted) and the strength of the basic sites, as well as the nature of the metallic function of the supported metal catalysts obtained from LDH is discussed. It is emphasized on the equilibrium between the basic and metallic functions required to reach high activities and selectivities.     

The interaction of rutile (TiO2) surface with some catalytically active transition metal oxides during heating,studied by electrochemical methods

The interaction of the surface of a rutile monocrystal (110 oriented) with the oxides of some transition metals (V, Mo, Cr, Mn and Nb) during heating of the crystal with these oxides was investigated by electrochemical methods. In all cases insertion of the metal atoms in the rutile surface was observed, the degree of insertion depending strongly on the metal in question and the conditions of experiment. The interaction of rutile surface with metal oxides changes dramatically the conditions of charge transfer at the rutile surface, which may influence the course of catalytic reactions occurring at the surface of rutile-supported transition metal oxide catalysts. This revised version was published online in June 2006 with corrections to the Cover Date.     

High-resolution scanning electron microscopy for the characterization of supported metal catalysts

A scanning electron microscope with a short-focal-length immersion lens and subnanometer resolution has been used to characterize several oxide-supported metal particle catalysts. Nanometer-sized metal particles in the Pt/TiO₂ and Pd/SiO₂ systems could be imaged with best clarity at the upper end of the operating voltage range (20–30 kV). However, visibility depended upon an adequate yield of secondary electrons relative to the support: small Pt particles on CeO₂ could not be located by secondary electron imaging. Best visibility of the surface topography of the support was obtained at lower accelerating voltages.     

苯乙烯环氧化制环氧苯乙烷的催化剂研究进展

介绍苯乙烯环氧化制取环氧苯乙烷的几种催化体系,重点叙述了Mn、Ag、Ti、Co、Fe等负载型催化剂,同时介绍了具有巨大潜力的席夫碱金属配合物催化剂的前景。