以次磷酸钠为还原剂化学镀铜的电化学研究

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.     

Electrodeposition, Structure and Corrosion Resistance of Nanocrystalline Ni-W Alloy

Ni—W alloy was electrodeposited from the electrolyte solution containing sodium tungstate, nickel sulfate and ammonium citrate. The electrodeposition, heat treatment, structure, surface morphology and corrosion resistance in w=0.03 NaCl solution, of Ni-W alloys were studied by means of DSC, XRD, SEM and electrochemical techniques. The results showed that the obtained Ni-W alloy electrodeposit with W weight content (Ww=0.471) was presented in more typical nanocrystaUine, After heat treatment at 400 ℃ for 1 h, the phase structure of the deposits was not obviously changed whereas the agglomerate for the reunion of tiny grains on deposit surface caused the granule in a more smooth morphology, the microhardness was slightly increased and the corrosion resistance was enhanced.     

碱性介质中高择优取向（220）镍电极上乙醇的电氧化

碱性介质中高择优取向（220）镍电极上乙醇的电氧化;高择优取向镍电极;电沉积;乙醇;电氧化;现场红外反射光谱     

有机介质中辅酶NADH的电化学氧化

用伏安法分别研究Ｎ,Ｎ′－二甲基甲酰胺和１,４－二氧六环介质中还原态烟酰胺辅酶ＮＡＤＨ在玻碳电极上的电化学氧化行为并测定某些动力学参数。ＮＡＤＨ的电氧化表现为完全不可逆过程,实验证明其过程伴有快速化学步骤。与在１,４－二氧六环介质中的相比,ＮＡＤＨ在Ｎ,Ｎ′－二甲基甲酰胺介质中的电氧化速度和扩散系数较小,但电流响应较为稳定。根据溶剂效应讨论了上述实验结果。     

FeCl_2-K_2MoS_4体系电催化还原乙炔为乙烯

采用控电位电解、循环伏安法和交流阻抗法研究了FeCl_2-K_2MoS_4体系对乙炔在石墨电极上还原为乙烯的电催化活性及反应机理。实验结果表明,当石墨阴极的电位控制在-1.50V(vs.SCE)时,FeCl_2+K_2MoS_4的DMF溶液对C_2H_2还原为C_2H_4表现出明显的电催化活性和高的选择性。在-0.5～-1.0V时Mo(Ⅵ)还原为Mo(Ⅴ);在按连串的电子传递机理进行的Mo(Ⅴ)→Mo(Ⅲ)反应的电位区间(-1.0～-1.50V)溶液中所形成的络合品种传递电子的能力更强。Mo(Ⅲ)可能是络合物的电活性成分。     

Ni—Mo—PTFE复合电极的制备及其对甲醇电氧化的催化性能

在０．２２ｍｏｌ／Ｌ硫酸镍，０．０６ｍｏｌ／Ｌ钼酸钠，０．３ｍｏｌ／Ｌ柠檬酸钠，３０ｇ／ＬＰＴＦＥ乳液，０．１ｇ／ＬＦＣ－４００表面活性剂的电解液（ｐＨ＝９）中，于温度４５℃，通以１０ｍＡ／ｃｍ２的电流，在纯Ｃｕ片上沉积出Ｎｉ－Ｍｏ－ＰＴＦＥ复合沉积层，ＸＲＤ、ＸＰＳ表征结果表明，该复合沉积层属立方晶系，其点阵型式为面心点阵Ｆ，晶胞参数ａ为０．３５７３ｎｍ，镍钼合金为固溶体结构，其（１１１）织构度ＴＣ（１１１）为６８％，表明该沉积层呈（１１１）择优取向．沉积层表面的氟以（ＣＦ２）ｎ的形式存在，ＳＥＭ观察结果表明沉积层含有ＰＴＦＥ时表面的粗糙度增大．镍－钼－ＰＴＦＥ复合电沉积过程经历吸附态物种氢氧化镍和钼的氧化物，它们继续捕获电子被还原为镍钼合金，ＰＴＦＥ粒子以包埋的形式沉积于镀层中．循环伏安结果表明该复合电极在ＮａＯＨ溶液中对甲醇的电氧化具有催化活性．     

非晶态Ni-W-B合金的电沉积及其热处理前后的性能

To strengthen the properties of Ni-W alloy, dimethylamine borane （DMAB） was added to an alloy Ni-W electrolyte solution and a ternary Ni-W-B alloy was electrodeposited. The electrodeposition, crystallographic structure, surface morphology, heat treatment and corrosion resistance, of the alloy were studied by DSC, XRD, SEM and electrochemical techniques. The results showed that the structure of the alloy was greatly affected by the cooperation of boron compound. DSC experiment combined with X-ray diffractometry indicated that the obtained Ni-W-B alloy was still in amorphous structure although W content in the alloy was decreased by the addition of DMAB. After heat treatment at 400 ℃ for 1 h, the microhardness was increased from 612 to 947 kg.mm^-2 that was com- parative to Cr coating. The appearance of the as-plated coating was in f＇me and slice grains and kept almost no change after heat treatment. In w=0.03 NaC1 solution the as-plated coating presented very good corrosion resistance. After the coating was heat-treated its corrosion resistance was enhanced.     

电沉积非晶态Ni-W-B/ZrO2复合镀层及其结构与性能

在含有二氧化锆的Ni-W-B电解液中，电沉积获得Ni-W-B/ZrO2复合镀层.用差示扫描量热分析(DSC)、X射线衍射(XRD)、扫描电子显微镜(SEM)和电化学技术较系统地研究了Ni-W-B/ZrO2复合镀层的电沉积、热处理过程，以及镀层的结构、表面形貌、显微硬度和耐腐蚀性能.结果表明, 复合镀层的质量组成为Ni 47.5％、W 40.9％、B 0.9％和ZrO2 10.7％. DSC和XRD结果清楚说明, 二氧化锆对基质Ni-W-B镀层的结构有明显影响, 使得复合镀层的非晶态结构特征更加明显 .复合镀层比Ni-W-B合金有更高的显微硬度, 呈现团粒状结构, 晶块之间不存在裂纹但晶界清晰可辨; 二氧化锆粒子分散于Ni-W-B基质镀层中. 400 ℃、1 h热处理后, Ni-W-B基质镀层中W向镀层表面偏析, 镀层呈现固溶体晶态结构特征, 表面形貌特征基本不变, 复合镀层的显微硬度进一步提高, 抗腐蚀性能增强, 但镀层表层中的二氧化锆粒子大量脱落.     

添加剂作用下钯电沉积行为研究

在含有4 g•L－1 Pd(NH3)2Cl2和104 g•L－1 NH4H2PO4的闪镀钯基础电解液中,采用极化曲线、循环伏安法和计时安培法研究添加剂作用下钯在玻璃碳电极上的电沉积和电结晶行为.结果表明,添加剂阻化钯的电沉积;钯在玻碳电极上的交换电流密度很低;钯电沉积过程经历了晶核形成过程,其电结晶机理在不含添加剂时接近于三维连续成核,含添加剂时接近于三维瞬时成核.