An Electroless Copper Plating Process Using Glyoxylate as Reductant

研究了以乙醛酸为还原剂的化学镀铜工艺、镀层结构和形貌。其镀液组成和操作条件为:28.0 g/l CuSO4.5H2O,44.0 g/l EdTA-2nA,10.0 Mg/lα,α'-联吡啶,10.0 Mg/l亚铁氰化钾,9.2 g/l乙醛酸,PH为11.5~12.5,θ为40~50℃。实验结果表明,化学镀铜溶液较稳定;镀液温度和硫酸铜质量浓度提高,铜沉积速率增大;较高的镀液温度下,化学镀铜反应的活化能较低,镀液稳定性下降;镀液PH在11.5~12.5可获得较好的铜镀层;随乙醛酸和络合剂质量浓度提高,铜沉积速率变化不大,但过量的乙醛酸导致镀液的稳定性降低;铜镀层为面心立方混晶结构,呈光亮的粉红色块状形貌,有较高的韧性。An electroless copper plating process using glyoxylate as reductant was developed,structure and surface morphology of the deposit were also studied.The bath composition and operating conditions were:28.0 g/L CuSO4 · 5H2O,44.0 g/L EDTA · 2Na,10.0 mg/L α,α'-bipyridyl,10.0 mg/L potassium ferrocyanide,9.2 g/L glyoxylate,pH 11.5--12.5,temperature 40--50 ℃.Experimental results showed that:the electroless copper plating bath was quite stable;the copper deposition rate would increased in case of bath temperature and copper sulfate concentration increased;the bath stability would decreased due to lower activation energy of copper deposition in case of higher temperature;the qualified copper coating could be obtained only at a proper bath pH range of 11.5--12.5;the copper deposition rate would not be affected by concentrations of glyoxylate and complexing agent evidently,whereas excessive content of glyoxylate would cause the bath stability decreased;the copper coating had a FCC mixed crystal structure with blocky grains、pink/bright appearance and good ductility.国家自然科学基金(20873114;20833005);国家重点基础研究发展规划项目(973)(2009CB930703

纳米TiO_2电极的特殊光电化学响应

应用涂膜法、电沉积法和溶胶-凝胶法制备纳米TiO2电极.实验发现,纳米TiO2具有特殊的光电化学响应,其光电流~电位变化出现光电流峰,这一特殊的光电化学性质乃与纳米半导体电极的纳米结构及其特殊的光诱导氧化还原反应机理密切相关

钾修饰的MoO_3/SiO_2催化剂的XRD和TPR表征

采用XRD和TPR测试技术表征了一系列不同K与Mo摩尔比的MoO3/K2O/SiO2催化剂。XRD表征结果显示,随着元素K的加入,多钼物种逐渐被破坏,最终形成了单钼的K2MoO4物种。TPR表征显示,催化剂表面的钼物种有2种结构,即八面体的Mo(Oh)和四面体的Mo(Td)。八面体Mo(Oh)的还原峰在770 K附近,而四面体Mo(Td)还原峰在1 000 K附近;无K的MoO3/SiO2催化剂的低温还原峰出现在840 K,少量元素K的添加削弱了Mo与SiO2之间的作用,使得低温还原峰温度降低到770 K附近;随着元素K添加量的进一步增加,Mo(Oh)物种逐渐减少而Mo(Td)物种逐渐增多,从而使得催化剂表面的Mo更难被还原。高硫合成气制甲硫醇的活性随着钼基催化剂八面体(Oh)钼物种的增加而增加

Cyanide-free copper electroplating in sulfite/thiosulfate bath

采用黄铜和不锈钢为基体,以SO 32-/S 2 O32-为还原剂和配位剂,胺化合物为配位剂,研究了一价铜无氰镀铜工艺,其镀液组成和操作条件为:CuCl2.2H2O 16.0--21.3 g/l,232SO-/S 2 O3-0.475 MOl/l,胺化合物0.76 MOl/l,H3bO3 36 g/l,葡萄糖0.38 MOl/l,光亮剂(有机胺类化合物)0.04 Ml/l,温度40°C,PH 8(以kOH调节),搅拌,电流密度0.5--2.0 A/dM2。讨论了温度、PH、铜离子质量浓度和光亮剂体积分数对镀层质量及电流效率的影响,分别采用扫描电镜和X射线衍射表征了镀层的表面形貌和结构。结果表明,控制合适的条件可使电流效率超过90%。使用本工艺电镀时,应采用较高的镀液PH,但镀液在存置时宜控制在较低的PH。添加剂能提高镀液的整平性能,使铜镀层只出现(111)和(200)晶面,光亮度提高,晶粒更细小、致密,颗粒分布均匀。A cyanide-free copper electroplating process with sulfite/thiosulfate as reducing and complexing agents,amine compound as complexing agent and cuprous ions as main salt was studied using brass and stainless steel as substrates.The bath composition and operation conditions are CuCl2.2H2O 16.0-21.3 g/L,sulfite/thiosulfate 0.457 mol/L,amine compound 0.76 mol/L,H3BO3 36 g/L,glucose 0.38 mol/L,brightener(organic amine compound) 0.04 mL/L,temperature 40 °C,pH 8(adjusted with KOH),agitation,and current density 0.5-2.0 A/dm2.The effects of temperature,pH,mass concentration of copper ions and volume fraction of brightener on the deposit quality and current efficiency were discussed.The structure and surface morphology of the deposit were characterized by SEM and X-ray diffraction,respectively.The results showed that the current efficiency can reach over 90% by appropriately controlling the conditions.The bath pH should be relatively high in operation,but relatively low during storage.The additive can improve the leveling performance of the bath,lead to the unique formation of(111) and(200) oriented faces of copper deposit,increase the deposit brightness,and make grains smaller,more compact and more uniformly distributed.广东省教育部产学研结合专项资金项目(2006D90404019);福建省科技计划重点项目(2008H0086);国家自然科学基金项目(20873114

Comparison between the Electroless Copper Plating Processes Using Sodiu m Hypophosphite and For maldehyde as Reductants

比较并评价了以甲醛和以次磷酸钠为还原剂的化学镀铜工艺。结果表明,次磷酸钠镀铜液的稳定性高于甲醛镀铜液,次磷酸钠镀液的沉积速率高于甲醛镀液。以甲醛为还原剂的镀层晶粒细小,而以次磷酸钠为还原剂的镀层呈团粒状。甲醛镀铜层铜的质量分数接近100%,次磷酸钠镀铜层中铜的质量分数为93.9%,镍的质量分数为6.1%,镀层为铜-镍合金。以甲醛为还原剂的化学镀铜层的电导率、抗拉强度、延伸率等物理性能均优于次磷酸钠化学镀铜层。The processes of the electroless copper plating using sodium hypophosphite and formaldehyde as reductants were compared and evaluated.The results show that the electrolyte using sodium hypophosphite as reducing agent is more stable than that using formaldehyde as reducing agent;the electroless deposition rate of the sodium hypophosphite solution is higher than that of the formaldehyde bath;the deposit grains are very fine and dense when using formaldehyde as reductant,and the other is of agglomerate morphology;the copper content in formaldehyde's deposit is nearly 100%(wt),and the deposit from sodium hypophosphite bath contains 93.9%(wt) copper and 6.1%(wt) nickel;the conductirity,tensile strength and ductibility of formaldehyde's deposit are better than that from the sodium hypophosphite solution.国家科技攻关计划资助项目(2004BA325C

Charge Transport Performance of Nafion-based Redox Polymer in Atmosphere

利用三明治电池和伏安法测试了不同制备条件的Nafion基氧化还原聚合物膜在空气中的电荷传输性能.研究结果表明,混合适量聚乙二醇(PEG)的Nafion基金属联吡啶配合物｛Nafion[M(bpy)23+,PEG](M=Ru,Fe)｝膜的表观电荷传递扩散系数(Dct)达到10-6-10-7cm2·s-1,电子或空穴迁移率(μ)达到10-4-10-5cm2·V-1·s-1.在导电玻璃(ITO)电极与Nafion基氧化还原聚合物膜界面引入一层导电聚苯胺(PANI)后,降低了其接触电阻,使氧化还原聚合物膜的Dct提高至10-5-10-6cm2·s-1,μ提高至10-3-10-4cm2·V-1·s-1,且工作电流提高了近两个数量级.该固态氧化还原聚合物膜的性能比较稳定,在空气中放置30天后其Dct和μ降低得很少.The charge transport performance of the Nafion-based redox polymer films prepared under different conditions was investigated by cyclic voltammetry in the sandwiched cells.The results showed that the apparent charge transfer diffusion coefficient(Dct)of the Nafion[M(bpy)2+3,PEG(polyethylene glycol)](M=Ru or Fe)films is about 10-6-10-7 cm2·s-1 and the mobility of the electron or hole(μ)was about 10-4-10-5 cm2·V-1·s-1.In order to decrease the resistance of the interface,a polyaniline(PANI)layer was added to the interface of indium tin oxide coated conducting glass(ITO)electrode and the redox polymer.Consequentially,the Dct could be increased to about 10-5-10-6 cm2·s-1 and μ to about 10-3-10-4 cm2·V-1·s-1,and the operating current of the cells under 600 mV bias could be increased by almost 100 times.In addition,the Dct and μ of this redox polymer film had just reduced slightly after 30 d kept in atmosphere.Therefore,the redox polymer film is sufficiently stable.国家自然科学基金(20373057)资助项

Charge transport performance of Nafion-based redox polymer in atmosphere

The charge transport performance of the Nafion-based redox polymer films prepared under different conditions was investigated by cyclic voltammetry in the sandwiched cells. The results showed that the apparent charge transfer diffusion coefficient(D-a) of the Nafion[M(bpy)(3)(2+), PEG (polyethylene glycol)] (M=Ru or Fe) films is about 10(-6)-10(-7) cm(2) . s(-1) and the mobility of the electron or hole (mu) was about 10(-4)-10(-5) cm(2) . V-1 . s(-1). In order to decrease the resistance of the interface, a polyaniline (PANI) layer was added to the interface of indium tin oxide coated conducting glass (ITO) electrode and the redox polymer. Consequentially, the D-a could be increased to about 10(-5)-10(-6) cm(2) . s(-1) and mu to about 10(-3)-10(-4) cm(2) . V-1 . s(-1), and the operating current of the cells under 600 mV bias could be increased by almost 100 times. In addition, the D-a and mu of this redox polymer film had just reduced slightly after 30 d kept in atmosphere. Therefore, the redox polymer film is sufficiently stable

Selenium-Decorated Graphene for Peroxynitrite Detection

Peroxynitrite (PON, ONOO−) is a member of the reactive oxygen-nitrogen species family. PON is generated in vivo by the diffusion-limited reaction (~2×1010 M−1S−1) of nitric oxide (·NO) and superoxide (O2·−) radicals. Elevated peroxynitrite levels are associated with several human pathologies, such as arthritis, inflammation, and carcinogenesis, as well as ageing-associated diseases. Thus, the precise detection of this species in biological systems is crucial, not only to understand the genesis and causes of ailments at the tissue/cellular level, but also to suggest and design potential therapies. The essential trace element selenium (Se) is the catalytic cofactor of important endogenous antioxidative systems of the human body. In the past decade, selenium attracted the attention of many research groups for the understanding of fundamental biological functions and biomimetic applications. Selenium is found in several human proteins (selenoproteins), many of them involved in anti-oxidant defense systems. Therefore, selenium plays a key role in redox regulation as a modulator of reactive oxygen species (ROS). Recently, a number of novel synthetic organoselenium compounds has been prepared and used as antioxidants in medicinal chemistry such as ebselen. In this work, we prepare and investigate interfaces based on the electrochemical deposition of selenium nanoparticles. We prepared surfaces of electrodeposited elemental selenium (Se) and selenium-decorated graphene-based nanostructures on glassy carbon electrodes and carbon fiber microelectrodes. We have used several physicochemical methods to characterize these PON-sensitive interfaces, including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX), X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy, and UV-vis on ITO transparent electrodes. We tested these interfaces for electrocatalytic sensing of peroxynitrite. We found that selenium-modified graphene platform is sensitive to peroxynitrite in solution, and it provides a viable interface for electrochemical sensing of this analyte. We observed that there is a synergistic effect of the presence of graphene as a substrate for selenium nanoparticles in the electrocatalytic detection of PON. In this paper, we will present our findings using this new PON-sensitive interface. We will compare and contrast the performance of the various modified carbon electrodes in terms of PON sensitivity using cyclic voltammetry and dose-response chronoamperometry

肝素-琼脂糖凝胶6FF的制备及其在抗凝血酶III分离纯化中的应用

以自制琼脂糖凝胶6FF为基质,肝素为配基,利用还原胺化方法制备了肝素-琼脂糖凝胶6FF介质.考察了肝素偶联反应的影响因素,并对其进行了优化,得到肝素配基的含量为2.7mg/mL.用所制介质从人血浆中分离出抗凝血酶III,从血浆开始计算的抗凝血酶III活性回收率为31.76%,与商品Heparin-SepharoseCL-6B的分离效果相当