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1.
分别采用化学镀铜法、化学还原法、浸渍法制备了3种Cu负载的S-TiO2光催化剂,综合利用UV-Vis、XRD、XPS、EXAFS、SEM和FESEM技术对制备的Cu/S-TiO2光催化材料的结构和光电子性能进行了表征.结果表明,化学镀铜法和浸渍法负载的铜物种为Cu2O和CuO,化学还原法制备的铜为Cu和Cu2O.化学镀铜法制备的Cu/S-TiO2光催化剂不仅对可见光具有很强的吸收能力,而且负载的铜物种连续、均匀地分散在S-TiO2表面,这种结构有利于光生电子的捕获、转移和分离.因此,化学镀铜法制备的Cu/S-TiO2在不同可见光波段(λ>420 nm,λ>500 nm)条件下光催化重整甲醇水溶液制氢反应中都表现出最高的催化活性,同时在模拟太阳光条件下以及稳定性实验的测试中也表现出优秀的性质,因此对其催化作用/反应机理进行了探讨.  相似文献   

2.
粉末化学镀法制备NiB/NaBETA催化剂及其加氢催化性能   总被引:3,自引:0,他引:3  
粉末化学镀法制备NiB/NaBETA催化剂及其加氢催化性能;非晶态合金催化剂  相似文献   

3.
以TiO2为载体,N iB为诱导剂,粉末化学镀法制备了负载型纳米N i催化剂.通过TEM、HRTEM、XRD和ICP技术对催化剂物性进行了表征.结果表明,碱性镀液可使载体表面均匀负载微晶结构纳米N i团簇,尺度为35nm左右.该负载型纳米N i在对氯硝基苯选择加氢反应中表现出很高催化加氢活性,并能有效抑制脱氯,达到了工业骨架镍水平.由酸性镀液得到的负载型非晶态纳米N i-P合金具有较弱的催化对氯硝基苯加氢活性.反应温度对反应时间和脱氯率有明显影响.  相似文献   

4.
This report describes the fabrication and electroless plating of regular porous and pincushion-like polymer structures prepared by self-organization. Honeycomb-patterned films were prepared by simple casting of polymer solution under applied humid air and pincushion structures by peeling off the top layer of the former films. Silver-deposited honeycomb-patterned films and pincushion films were obtained by simple electroless plating of the respective original structures. XPS revealed Ag deposition on the honeycomb-patterned film. After thermal decomposition or solvent elution of the template polymer, unique metal mesoscopic structures were obtained.  相似文献   

5.
粉末化学镀负载型NiB/MgO非晶态合金及其加氢催化性能   总被引:1,自引:0,他引:1  
粉末化学镀负载型NiB/MgO非晶态合金及其加氢催化性能;NiB/MgO;非晶态合金;粉末化学镀;环丁烯砜加氢  相似文献   

6.
总结自大马士革铜工艺建立以来,电化学工作者利用化学镀技术围绕该工艺而开展的一系列相关研究,介绍了应用化学镀沉积镍三元合金防扩散层和化学镀铜种子层的研究以及离子束沉积法(Ion ized C lus-ter Beam,ICB)形成Pd催化层后的化学镀铜技术和超级化学镀铜方法.简要叙述化学镀铜技术在超大规模集成电路中的应用,总结化学镀铜技术的研究进展,并指出了今后的发展方向.  相似文献   

7.
碳纳米管表面的无钯活化化学镀镍研究   总被引:2,自引:0,他引:2  
本文提出碳纳米管表面无钯活化的化学镀镍方法.碳纳米管经硝酸氧化和碱中和后表面生成羧基,利用羧基吸附镍离子,之后吸附的镍离子被化学还原为镍的纳米微粒并成为化学镀镍的催化活性中心.红外吸收光谱和电子显微镜观察等证实了上述活化过程的机理.实验表明,新的活化方法对碳纳米管表面化学镀是切实可行的,文中同时对化学沉积层的不同形貌进行讨论.  相似文献   

8.
This article reviews our works on the structured catalysts for a wall-type hydrogen production system including methanol steam reforming (MSR), CO shift reaction (CO SR) and methanol decomposition (MD). The structured catalysts were copper-based, palladium-based and nickel-based catalysts. Such a series of structured catalysts were prepared by the electroless plating technique that is a novel method for preparing a structured type catalyst onto a metal-substrate. The copper-based catalyst exhibited high performance for MSR and CO SR, the palladium-based catalyst high for MSR, and the nickel-based catalyst high for MD. The catalytic properties of these catalysts were affected by the difference of the plating condition and the pretreatment condition prior to the reaction. In the copper-based catalyst, the reforming and shift activities were enhanced by the oxidation treatment. One of the factors of such activity enhancement by the oxidation was thought to be in close proximity existence of copper and zinc atoms. A lot of monodentate-type formate species having high reactivity was formed on the oxidized catalyst, which would be correlated to the activity enhancement. In the palladium-based catalyst, the reforming activity was improved by the continuous reduction treatment followed by the oxidation. Such continuous pretreatment formed the PdZn alloy species thought to be a reforming site in the surface layer. The decomposition performance of the nickel-based catalyst depended on the ratio of the crystallite size of nickel particles to that of aluminum particles. The electronic influence of zinc and phosphorous components incorporated in the plated layer contributed to the improvement of the selectivity of product.  相似文献   

9.
采用浸渍法制备了Al2O3负载的5种过渡金属氧化物催化剂,考察了它们在常温下催化臭氧氧化甲苯的性能,并运用程序升温还原、程序升温氧化、N2吸附-脱附和X射线光电子能谱对催化剂进行了表征.结果表明,NiO/Al2O3,CoO/Al2O3和MnO2/Al2O3催化剂上活性氧中心数量较少,臭氧与甲苯转化率较高;而Fe2O3/...  相似文献   

10.
Pd基无涂层整体式催化剂上甲苯催化燃烧净化研究   总被引:5,自引:2,他引:3  
采用化学镀法在堇青石蜂窝陶瓷基体上制备了Pd基无涂层整体式催化剂Pd/cord,并对其在甲苯催化燃烧净化反应中的催化性能进行了研究.结果表明,Pd/cord催化剂在钯负载量较低(如为0.24%)时,即可使甲苯从201℃起燃后,突跃到226℃完全转化,表现出良好的甲苯催化燃烧净化性能.该类催化剂在空速6000h-1 ~4...  相似文献   

11.
通过乙醇催化燃烧法制备了碳纳米纤维(CNFs),采用化学沉积法在CNFs载体上负载铁钴镍硼化物(FeCoNiB),并以多种测试手段对其表征,研究了化学沉积工艺条件对FeCoNiB粒径、分散、成分及结构的影响,建立了碳纳米纤维负载的铁钴镍硼化物(FeCoNiB/CNFs)可控制备方法。采用电化学测试手段研究了FeCoNiB/CNFs在碱性环境下的氢气析出反应(HER)催化性能。结果表明,在100 mA/cm2的电流密度下,FeCoNiB/CNFs的过电位仅为366 mV,塔菲尔斜率低至41 mV/dec;在持续10 h的稳定性测试中电位衰减幅度很小,基本保持不变。这说明FeCoNiB/CNFs制备成本低,但其高稳定性可媲美贵金属的高催化活性HER催化剂;该研究可为非贵金属HER催化剂的研制及低成本电解水制氢技术的规模化应用提供参考。  相似文献   

12.
自组装膜吸附钯的化学镀前活化研究   总被引:9,自引:0,他引:9  
提出了一种无需氯化亚锡敏化、基于分子自组装膜(SAMs)吸附钯的活化方法,成功地引发了在氧化铝粉末表面的化学镀铜.用XPS、AES、FTIR研究了钯的吸附机理,认为是由于氯化钯与SAMs上向外突出的氨基形成了化学键,并提出了相应的活化机理.金属化产物经XRD、FTIR、剖面金相显微表征分析与压片电阻率测定,示为金属铜完全包覆氧化铝的复合材料.该活化工艺具有活性引发层厚度薄、寿命长和与基底结合力强等优点,也可应用于其它表面富羟基的基底材料.  相似文献   

13.
以次磷酸钠为还原剂化学镀铜的电化学研究   总被引:7,自引:0,他引:7  
通过电化学方法研究了以次磷酸钠为还原剂, 柠檬酸钠为络合剂的化学镀铜体系. 应用线性扫描伏安法, 检测了温度、pH值、镍离子含量对次磷酸钠阳极氧化和铜离子阴极还原的影响. 结果表明, 升高温度能够加速阳极氧化与阴极还原过程; pH值的提高可促进次磷酸钠氧化, 但抑制铜离子还原; 镍离子的存在不仅对次磷酸钠的氧化有强烈的催化作用, 而且与铜共沉积形成合金. 该合金有催化活性, 使化学镀铜反应得以持续进行.  相似文献   

14.
蔡豪坤  张健  鹿萍  雷克微  董坚 《应用化学》2015,32(8):892-899
以高分子微凝胶为载体, 先通过浸渍法在载体上引入少许的镍金属种子, 再通过化学法镀镍, 在种子载体上镀上大量镍, 制备出微凝胶负载Ni催化剂。 以水合肼为氢给体, 使用此类催化剂催化还原芳香族硝基化合物呈现出较高的活性。 经动态光散射法检测, 这种微凝胶催化剂的流体力学直径为411.9 nm。 高分辨透射电子显微镜和X射线光电子能谱分析表明, 所制得的催化剂中Ni主要是以NiO的形式存在。 以硝基苯为原料考察了水合肼的用量对反应的影响, 结果表明, 底物与水合肼的摩尔比为1:15最佳。 在优化条件下, 硝基苯衍生物的还原均能得到高产率的芳香胺。 动力学研究结果表明, 硝基苯氢转移反应的活化能为133.7 kJ/mol, 焓变为130.9 kJ/mol, 熵变为102.8 J/(mol·K)。  相似文献   

15.
Ni-P化学镀反应速率及机理研究   总被引:7,自引:0,他引:7  
通过镀层分析和析氢量测量得到Ni-P镀层的沉积速度和H2PO2的分解速度·以混合电位理论为基础,对Ni-P电极在不同组成饮液中的极化曲线进行分解得到以化学镀电流形式所表示的反应速率·将两种方法所得结果进行对照,确定H2PO2氧化时电子迁移数为1,并用原子红-电化学联合理论解释溶液PH对反应速率及化学镀效率的景响.  相似文献   

16.
Nickel nanoparticles supported on metal oxides were prepared by a modified electroless nickel-plating method. The process and mechanism of electroless plating were studied by changing the active metal (Ag) loading, acidity, and surface area of metal oxides and were characterized by UV–vis spectroscopy, transmission electron microscopy, scanning electron microscopy, and H2 chemisorption. The results showed that the dispersion of nickel nanoparticles was dependent on the interface reaction between the metal oxide and the plating solution or the active metal and the plating solution. The Ag loading and acidity of the metal oxide mainly affected the interface reaction to change the dispersion of nickel nanoparticles. The use of ultrasonic waves and microwaves and the change of solvents from water to ethylene glycol in the electroless plating could affect the dispersion and size of nickel nanoparticles.  相似文献   

17.
于Ni-P镀液添加TiO2颗粒,用化学镀法在黄铜基底上制备不同TiO2含量的Ni-P-TiO2复合镀层电极.采用循环伏安法、线性扫描法、计时电流和交流阻抗法测定Ni-P-TiO2/Cu电极的电化学性能.结果表明:常温下Ni-P-TiO2/Cu电极在碱性溶液中对乙醇氧化有很高的电催化活性;Ni-P-TiO2电极上乙醇的电催化氧化活性随镀层TiO2量的不同而异;镀液中TiO2含量为5 g.L-1时,所得电极的电催化乙醇氧化的活性最佳.  相似文献   

18.
The bottom‐up filling capabilities of electroless copper plating bath with an addition of additives, such as polyethylene glycol (PEG), polypropylene glycol (PPG) and triblock copolymers of PEG and PPG with ethylene oxide terminal blocks termed EPE, were investigated by the cross‐sectional scanning electron microscopy (SEM) observation of sub‐micrometer trenches. Though three additives had inhibition for electroless copper deposition, the suppression degrees of three additives were different. EPE‐2000 had the strongest suppression for electroless copper deposition, and the suppression of PEG‐2000 was the weakest. The bottom‐up filling capability of electroless copper was investigated in a plating bath containing different additives with the concentration of 2.0 mg/L. The cross‐sectional SEM observation indicated the trenches with the width of 280 nm and the depth of 475 nm were all completely filled by the plating bath with an addition of EPE‐2000, but the trenches were not completely filled by the plating bath with an addition of PEG‐2000 or PPG‐2000, and some voids appeared. Linear sweep voltammetry measurement indicated that three additives all inhibited the cathodic reduction reaction and the anodic oxidation reaction, and the inhibition of EPE‐2000 was the strongest among three additives, which agreed with that of the deposition rate of electroless copper. Significant differences in surface roughness of deposited copper film were observed by UV‐visible near‐infrared for different suppressors, and the bright and smooth of deposited copper film were in accordance with the inhibition of three additives.  相似文献   

19.
We demonstrated that the photopatterned single-layer adsorption film of poly(1-dodecyl-4-pyridinium bromide) on a silica surface was available for a template of nickel-phosphorus (Ni-P) electroless plating through sensitization with a SnCl(2) aqueous solution and activation with a PdCl(2) aqueous solution. Four kinds of poly(1-alkyl-4-vinylpyridinium halide)s bearing methyl, propyl, hexyl, and dodecyl groups were prepared. The cationic polymers were adsorbed by a negatively charged silica surface from their solutions, to form single-layer adsorption films exhibiting desorption-resistance toward deionized water and ethanol. The organic adsorption films could be decomposed completely by exposure to 172 nm deep-UV light. The formation and decomposition of the single-layer films were confirmed by deep-UV absorption spectral measurement and zeta-potential measurement. Ni-P electroless plating was carried out on the photopatterned adsorption films, using three types of SnO(x) colloidal materials without and with cationic or anionic surfactant as catalyst precursors in the sensitization step. In the case of the negatively charged SnO(x) colloids surrounded by anionic surfactant, Ni-deposition took place preferentially on the cationic adsorption films remaining in unexposed regions. The Ni-deposition was accelerated significantly on the cationic adsorption film bearing dodecyl groups. It was obvious by ICP-AES analyses that the hydrophobic long-chain dodecyl groups in the adsorption film could promote the adsorption of the negative SnO(x) colloids on the film surface, followed by much nucleus formation of zerovalent Pd catalysts useful for the electroless plating. The result of our experiment clearly showed that, in addition to electrostatic interaction, van der Waals interaction generating between the hydrophobic long-chain hydrocarbons of the adsorption film and the surfactant improved significantly the adsorption stability of the SnO(x) colloids, resulting in highly selective Ni-deposition in accord with the photopattern shape of the cationic single-layer adsorption film.  相似文献   

20.
方景礼 《化学学报》1983,41(2):129-138
Electroless plating is known to be an autocatalytic process. For the reaction to start, the substrate metall should be either catalytic or activated by a suitable catalyst. For example, steel and nickel can be plated directly, but in the case of copper or brass, catalytic metal inducing is need. In this paper, the catalytic activity of different metals and their inducing effects were in vestigated by measuring stationary potentials nd stationary potential-time curves. Experimental results showed: (1) The stationary potential of metal provides a simple parameter to estimate the catalytic activity of metals in electroless nickeling. When 1-hydroxyethylidenediphosphonic acid (HEDP) aelectroless nickeling bath containing NaH2PO2 as reducing agent is used, electrolessnickeling may proceed spontaneously, if the stationary potential of metal is more nagative than -0.60V, no matter whether nickel (autocatalytic active) or other metals(non-autocatalytic active) is used as substrate. (2)When an autocatalytic meta is in contact with the substrate metal in the bath, a sudden decrease of stationary potential is observed. The whole inducing process could be finished within 0.5-2 sec. (3) The stationary potential of electroless nickeling coating in HEDP bath at 80`C is-0.72V, consequently nickel coating itself is a catalytic active metal. Once an electroless nickeling coating is deposited on a substrate metal, electroless nickeling reaction can then proceed continuously. (4) The sufficient conditions of electroless nickeling in HEDP bath containing NaH2PO2 are that the stationary potential of substrate metal must be more nagative than -0.60V and that the temperature of electroless nickeling bath should be higher than 50`C. (5) Inducing mechanism of electroless nickeling can be explained with chemical cell consisting of substrate metal and catalytic metal. Electrons from catalytic metal would suddenly decrease the stationary potential of substrate metal, H+ and Ni2+ complex ion would be reduced on the substrate me  相似文献   

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