载金催化剂前景看好

专家指出 ,载金催化剂因其具有特殊的性能 ,在化工、环保和汽车等领域有着广泛的使用价值。研究人员发现黄金可作为选择性加氢反应的催化剂 ,均匀地分散在催化剂载体上的微细粒金具有很高的催化活性。载金催化剂可以迅速地把一氧化碳氧化成二氧化碳、将氮氧化物还原。该类催化剂比其他任何能催化上述反应的催化剂的工作温度都低 ,最低可达 90 K( - 1 83℃ )。反应温度的降低 ,除对提高热效率和实现商业化有利之外 ,还可提高相关反应的选择性、减少副反应的发生。载金催化剂的另一个与众不同的优点是 ,它的催化活性随工作环境的湿度的升高而…     

含钼杂多酸型催化剂在有机合成中的应用

概述含钼杂多酸催化剂在有机合成中的应用，对这类杂多酸作为酸催化反应和氧化反应催化剂在烯烃水合、酯化、异构化、环氧化、醇类脱水、氧化等反应中的应用以及对可能的反应机理进行了讨论，并预测了该领域今后的发展方向。     

纳米TiO2催化超声降解酸性品红溶液的性能研究

采用处理过的市售的锐钛型和金红石型纳米TiO2作为催化剂，研究了各种因素对酸性品红超声降解反应的影响。结果表明在锐钛型纳米TiO2作用下超声降解酸性品红的效果明显优于金红石型纳米TiO2。超声波频率25kHz，输出功率50w，催化剂用量500mg／L，pH为3．0，酸性品红水溶液初始浓度10mg／L，的条件下，60min左右降解率即可达到80％以上，180min酸性品红基本可全部降解，COD的去除率也可达到了99．0％。因此，锐钛型纳米TiO2催化超声降解有机污染物的方法具有很好的应用前景。     

铑在均相催化工业中的应用

作为重要的催化材料,铑催化剂具有反应条件温和、反应选择性高等特点,已广泛应用于石油化工、医药化工、精细化工等领域。综述了铑作为加氢、氢甲酰化、羰基合成均相催化剂的工业应用情况的同时,还介绍了铑催化剂在新兴的不对称催化领域的选择催化性能和工业应用。指出了影响均相和手性铑催化剂工业化的因素,并对未来铑催化剂的工业应用进行了展望。     

大力开发黄金工业材料市场

与其它贵金属材料相比，黄金的价格近10年来基本稳定，主要是因为80％黄金用于珠宝饰物．工业应用仅占12％。为使黄金升值．必须大力培育和开发新的市场需求，主要有以下五个方面市场：①污染和废气控制技术（包括燃料电池）；②在先进电子和电学系统中的新应用；③金作为催化剂的化学反应过程；④先进的功能（纳米）涂料；⑤新的生物医学应用。黄金的许多新应用将在今后10年内逐渐出现，从而导致黄金市场的可持续增长。显然，许多新用途是基于化学合成，而不是传统的材料和机械工艺技术。文中重点介绍了金作为催化剂材料新的工业应用和研究开发现状，特别是一氧化碳（CO）低温氧化金催化剂。该催化剂可提高我军的装备现代化水平和战斗力，推广至消防和民用更具有重大意义。     

钌催化剂在有机合成中的应用

综述了钌催化剂催化的主要几类有机合成反应，包括氢化、氧化、异构化、复分解。重点介绍了钌催化剂催化选择性氢化反应和烯烃复分解反应的研究进展，指出了今后钌催化剂研究的几个重要方向，并对钌催化剂的工业应用前景作了展望。     

金纳米粒子的催化特性及其应用

金纳米粒子的特殊性质产生于其特殊结构及特殊效应。负载或非负载型Au纳米粒子表现出极高的化学活性和催化性能，使其在化学工业中得到了广泛应用。用沉积或共沉淀方式将Au纳米粒子负载到金属氧化物载体上，在室温催化氧化C0为C02的效率比其它贵金属催化剂高得多；Au／Ti02催化剂在气相中能够高效率地催化氧化丙稀为环氧丙烷，选择性高达90％；Au纳米粒子催化剂在不饱和碳氢化合物的部分氢化反应中表现出良好的选择性：非负载型和负载型Au纳米粒子在液相反应中表现出独特的催化特性;Au/Fe2O和Au/ZrO2等负载型催化剂在低温水气转换制备氢气的反应中催化活性很高，而且载体的结晶度越高，催化活性越高。中对近年来Au纳米粒子的上述催化特性和应用进行评述。     

以KBrO3为氧化剂液相氧化菲制菲醌

实验确定了以溴酸钾为氧化剂在醋酸介质中氧化菲成菲醌的较佳的反应条件：反应温度110℃、氧化剂配量2．25、底物菲的浓度为0．45mol／L．得到产物纯度为61．7％、产率为81．7％；探索了相转移催化剂在该反应中的应用．成功地开发了KBrO3-PTC-HAc-H2O氧化体系，确定采用TBA(四乙基溴化铵)作为相转移催化剂，反应温度为85℃，催化剂配量为1．25％，水的配量为6％，产品产率提高到88．2％，产品纯度为61．1％。     

石墨烯限域非贵金属单原子催化剂研究进展

石墨烯负载的非贵金属单原子催化剂有着特殊的晶格结构和物理化学性质，在多种化学反应中也具有优越的活性和选择性，以石墨烯作为催化剂载体时，单原子催化剂的整体性能得到显著提升，目前研究和开发高性能廉价的石墨烯限域非贵金属单原子催化剂是催化领域深入的关键。文章综述了近年来石墨烯限域非贵金属单原子催化剂的制备工艺、表征方法和应用方向。还介绍了其在CO₂氧化、析氢反应等催化反应中的应用。最后对石墨烯限域非贵金属单原子催化剂未来的发展方向进行了展望。     

中科院大连化物所金催化剂研究取得新进展

正近日,中国科学院大连化学物理研究所航天催化与新材料研究室(15室)和穆斯堡尔谱技术研究组(DNL2005)在金催化剂研究方面取得新进展。通过调节Au与羟基磷灰石(HAP)之间的金属—载体强相互作用(Strong Metal-Support Interaction,简称SMSI),成功设计并制备出具有高稳定性和高活性的金催化剂(Au/TiO_2-HAP)。在模拟汽车尾气CO消除反应中,该催化剂反应稳定性优于商业三效催化剂     

Pt?Au?Cu 三元核壳结构纳米线的制备与结构表征

通过水溶液还原法在80 ℃合成Cu纳米线，再利用液相还原法在低温水溶液中将Au负载于其表面，最后通过暴露的Cu纳米线与Pt前驱体盐发生Galvanic置换反应，将Pt负载在Au?Cu纳米线表面，构成Pt?Au?Cu三元核壳结构纳米线。根据对样品形貌、结构的表征和分析，探讨了Pt?Au?Cu纳米线的合成机理。结果表明:合成纳米线物相组成为单质Cu，平均直径约为83 nm；负载Au后的Au?Cu纳米线平均直径约为90 nm，表面附着的小颗粒为单质Au颗粒，构成了核壳结构；负载Pt后得到Pt?Au?Cu三元核壳结构纳米线，平均直径约为120 nm。Cu纳米线表面Au颗粒的形成依赖于异相形核与长大机制，并遵循先层状后岛状生长的混合生长模式。负载Pt过程中存在Pt、Cu互扩散，使得最终纳米线表面多为Pt颗粒而整体则形成CuPt 合金相。      

Construction of mesoporous ceria-supported gold catalysts with rich oxygen vacancies for efficient CO oxidation

Bearing unique redox nature and high oxygen storage capacity, ceria (CeO₂) has always been a promising CO oxidation catalyst support for gold (Au) catalysts and the like. Herein, a series of Au–CeO₂–P (P stands for pH value) samples was prepared by a co-precipitation method with the assistance of an alkaline environment and amino groups functionalized ordered mesoporous polymer (OMP-NH₂). Afterward, all samples described above were characterized that the Au–CeO₂–P catalysts are made of Au–Ce–O solid solution and Au nanoparticles (NPs) supported on CeO₂. It turns out that OMP-NH₂ is not just a simple sacrificial template for mesoporous structure, but also plays an important role as an amino source, explaining the presence of rich oxygen vacancies. Due to the concentration of oxygen vacancies in Au–Ce–O solid solution is the key factor for the oxygen mobility of CO oxidation, the catalytic results also demonstrate that the catalytic activity of Au–CeO₂–P catalysts is related to the concentration of their oxygen vacancies. Moreover, Au–CeO₂-9.6 with a highest concentration of oxygen vacancies (as high as 13.98%) in Au–CeO₂–P catalysts exhibits the best catalytic activity (complete conversion at 10 °C).     

A_2B_2O_7 pyrochlore compounds:A category of potential materials for clean energy and environment protection catalysis

A_2B_2O_7 pyrochlore is a kind of important functional materials for different purposes,which has been investigated extensively by crystallographers and material scientists.However,the catalytic chemistry of this type of special compounds has rarely been documented,though a few researchers have tried to synthesize some pyrochlore compounds with different chemical compositions for a variety of green energy production and air pollution control reactions in the history.With the expectation to help catalysis scientists to get better acquaintance with,and gain deeper understanding on this type of compounds as heterogeneous catalysts,the major publications over the past several decades have been screened and reviewed in this paper,based also on our own experience of studying on this type of catalytic materials.The crystalline phase transformations of the compounds with the change of the A and B site cations,the phase change's influences on the surface and bulk properties,and their subsequent impact on the catalytic performance for different reactions have been summarized.Furthermore,the future work which needs to be performed to perceive in depth this kind of important materials as catalysts has been proposed and suggested.We trust that this short review contains valuable information,which will provide great help for people to get better cognition for A_2 B_2 O_7 pyrochlore compounds,and assist them to develop better catalysts for various reactions.     

Effect of preparation method on the catalytic activity of Au/CeO2 for VOCs oxidation

The Au/CeO2 catalysts were synthesized by co-precipitation (CP), deposition-precipitation (DP) and metallic colloids deposition (MCD) method, and tested for oxidation of volatile organic compounds (VOCs). It was revealed that the Au/CeO2 catalyst prepared by DP method was the most efficient catalyst towards the total oxidation of toluene. The Au/CeO2 catalysts had obviously high catalytic activity, and the best results was obtained on 3 wt.% Au/CeO2 catalyst prepared by DP method. These catalysts were chara...     

Preparation of Au/CeO2 catalyst and its catalytic performance for HCHO oxidation

Aqueous precipitation and deposition-precipitation method were used to prepare CeO2 supports and Au/CeO2 catalysts, respectively. The effect of preparation condition of support on the catalyst activity was investigated. The catalytic combustion of HCHO was considered as the probe reaction for comparing the catalyst activity. The BET, X-ray diffraction, X-ray photoelectron spectroscopy （XPS）, and reduction （TPR） were carried out to analyze the influence factor on the catalysts activity. The results showed that the addition of dispersant and use of microwave in the support preparation procedure could be beneficial for enhancing the interaction of supports and gold species and thus improved the catalytic activity. The total conversion temperature for HCHO was 146 ℃ over AC400. With the modification during supports preparation process, the catalytic activity increased with total conversion temperature decreasing to 98 ℃. The results of XPS indicated that Au^0 and Au^＋1 species coexisted in these catalysts and the activity of catalyst correlated with Au^＋1/Au^0 ratio. Temperature-programmed reduction results demonstrated that the reduction peak appeared between 100-170 ℃ with the inducing of gold. The dependence of activity on the reduction peak temperature implied that ionic gold was catalytic activity component for HCHO oxidation.     

电解水制氢技术及大电流析氧反应研究与展望

当今时代对可持续能源的迫切需求推动了可再生能源技术的不断改进，其中氢能因其清洁环保且能量密度高而受到了科研人员广泛关注。电解水制氢作为一种绿色环保的制氢方式，其阳极析氧反应（OER）的高能耗限制了电解水制氢技术的广泛应用。近年来，高性能的OER催化剂的研究得到了长足发展，但催化剂的测试范围小，且很少能够连续工作数百小时，远远不能满足实际应用的需求。为了更好的适用于工业应用，OER催化剂需要满足更苛刻的测试环境，如在低过电位下提供大电流密度、在强气体排放过程中维持稳定性和耐久性，因此开发在大电流密度下的高活性OER催化剂是当前工作的重中之重。结合大电流OER催化剂的研究进展，本文首先提出氢能是目前最有前途的能源之一，并调研了大电流密度下电催化剂的研究现状。其次通过对OER机理进行分析，发现采取元素掺杂、界面工程、缺陷工程和形貌工程等措施可以提升催化剂在大电流密度下的活性。最后，对大电流析氧领域在工业发展中现阶段存在的挑战及未来发展方向进行了展望。      

用于木质素转化制备生物质燃料多功能催化剂的研究进展

综述了木质素加氢解聚、解聚单体加氢脱氧和单体升级为多环高价值产品等过程中所使用的多功能催化剂的研究进展,包括硫化物催化剂、贵金属单质催化剂、非贵金属单质和合金催化剂、磷化物催化剂等。强调了加氢催化剂（Ru、Pt、Pd、Co、Mo和Ni等）和酸催化剂（Al₂O₃、ZrO₂、NbOPO₄、沸石和介孔硅酸盐等）在加氢裂解、加氢脱氧和（加氢）烷基化反应中的协同作用。在此基础上总结了当前反应过程的一些难点,并对下一步的技术发展方向进行了展望。未来需要开发水热稳定性更好、价格更加低廉的高活性催化剂,降低氢气用量,同时考虑天然木质素的一锅法转化,为工业化制备生物质燃料奠定基础。      

Improvement of Gold to Reducibility of La-Ce-Mn Catalyst under Lean Combustion

The effect of Au on the reducibility of La-Ce-Mn catalyst was studied in the synthetic exhaust gas mixture containing 10% oxygen. The characteristics of samples were analyzed by BET, SEM, XRD and activity evaluation. The resuits show that, in lean combustion, the performance of perovskite-type catalysts is evidently enhanced through adding Au, and specially a satisfying reducibility for NOx is demonstrated between 300～500℃. The catalytic activity of samples increases with the loading amount of Au, and the maximum conversion rate for NOx decomposition reaches up to 47% in 360～400℃. Moreover, the dispersivity and uniformity of the surface distribution of perovskite with Au have an important influence on the catalytic activity.     

担载双金属催化剂对Heck反应的作用

制备了0．5％Pd／C催化剂和含钯担载双金属催化剂3％Cu．0．5％Pd／C，3％Mo-0．5％Pd／C，3％Ni-0．5％Pd／C，3％Co-0．5％Pd／C．3％Mn-0．5％Pd／C，用XRD法和XPS法进行了表征。结果表明，室温下，以KBH4还原剂制备的含钯担载双金属催化剂，在碘苯与丙烯酸的Heck偶合反应中，催化活性高于Pd／C（0．5h的转化率高，完成反应所需时问少），显示出添加贱金属的协同效应。其中，3％Mo-0．5％Pd／C显示出最高的催化活性，在0．5h时的转化率（67．4％）和收率（52．6％）比0．5％Pd／C分别高54．5％和42．2％，完成反应的时问最短，表明钼的协同效应最高。