合金电镀应用广泛,但将超声波用于合金电镀的研究还不系统。以超声波与电沉积相结合制备Pd-Ni-P合金,通过扫描电镜(SEM)、能谱仪(EDX)、X射线衍射仪(XRD)等对Pd-Ni-P合金镀层的形貌、成分和组织结构进行了表征,采用循环伏安法研究了超...合金电镀应用广泛,但将超声波用于合金电镀的研究还不系统。以超声波与电沉积相结合制备Pd-Ni-P合金,通过扫描电镜(SEM)、能谱仪(EDX)、X射线衍射仪(XRD)等对Pd-Ni-P合金镀层的形貌、成分和组织结构进行了表征,采用循环伏安法研究了超声波对Pd-Ni-P合金电沉积的影响。结果表明:超声波作用使沉积层中Pd的含量增加,镀层表面更致密均匀;超声波振荡有利于溶液中离子的传质过程,主要是提高了Pd2+的沉积速率;在1.0 mol/L Na OH溶液中,超声波作用显著增强了Pd-Ni-P合金镀层的耐腐蚀性能,使腐蚀电位正移80 m V。展开更多
We develop a unique ternary Pd-Ni-P nanocatalyst for the sensitive enzyme- free electrooxidation detection of glucose under alkaline conditions. By reducing the distance between the Pd and Ni active sites in the Pd-Ni...We develop a unique ternary Pd-Ni-P nanocatalyst for the sensitive enzyme- free electrooxidation detection of glucose under alkaline conditions. By reducing the distance between the Pd and Ni active sites in the Pd-Ni-P nanoparticles （NPs） via atom engineering, the catalyst structure is transformed from Pd@Ni-P dumbbells into spherical NPs, greatly enhancing the catalyst sensitivity. The glassy carbon electrode modified with Pd-Ni-P ternary NPs, which behaves as an efficient nonenzymatic glucose sensor, offers excellent electrocatalytic performance with a high sensitivity of 1,136 μA·mM^-1·cm^-2, a short response time of 2 s, a wide linear range of 0.5 μM to 10.24 mM, a low limit of detection of 0.15 μM （signal-to-noise ratio = 3）, and good selectivity and reproducibility. Moreover, owing to its superior catalytic performance, the Pd-Ni-P modified electrode has excellent reliability for glucose detection in real samples of human serum. Our study provides a promising alternative strategy for designing and constructing high-performance multicomponent nanocatalyst-based sensors.展开更多
The microstructure and solute distribution of Pd40Ni40P40 alloy solidified both on board a Chinese retrievable satellite (μg) and on the earth (1g) were studied. It was found that the dendritic primary phase formed u...The microstructure and solute distribution of Pd40Ni40P40 alloy solidified both on board a Chinese retrievable satellite (μg) and on the earth (1g) were studied. It was found that the dendritic primary phase formed under microgravity condition was finer and shorter. In the central area of the sample some asteroidal patterns of the primary phase were present in the microstructure. The primary spacing of the dendrites at the cooling rate of 0.056 K/s was smaller than that measured in the ground-based experiments at the same cooling rate, but almost the same as that cooled at 0.67 K/s on the ground. With these experimental results, mass transport coefficients both in space and on the earth were evaluated.展开更多
文摘合金电镀应用广泛,但将超声波用于合金电镀的研究还不系统。以超声波与电沉积相结合制备Pd-Ni-P合金,通过扫描电镜(SEM)、能谱仪(EDX)、X射线衍射仪(XRD)等对Pd-Ni-P合金镀层的形貌、成分和组织结构进行了表征,采用循环伏安法研究了超声波对Pd-Ni-P合金电沉积的影响。结果表明:超声波作用使沉积层中Pd的含量增加,镀层表面更致密均匀;超声波振荡有利于溶液中离子的传质过程,主要是提高了Pd2+的沉积速率;在1.0 mol/L Na OH溶液中,超声波作用显著增强了Pd-Ni-P合金镀层的耐腐蚀性能,使腐蚀电位正移80 m V。
基金This work was supported by the National Natural Science Foundation of China （Nos. 21475007, 21675009, and 21275015）. We also thank the support from the ＂Public Hatching Platform for Recruited Talents of Beijing University of Chemical Technology＂.
文摘We develop a unique ternary Pd-Ni-P nanocatalyst for the sensitive enzyme- free electrooxidation detection of glucose under alkaline conditions. By reducing the distance between the Pd and Ni active sites in the Pd-Ni-P nanoparticles （NPs） via atom engineering, the catalyst structure is transformed from Pd@Ni-P dumbbells into spherical NPs, greatly enhancing the catalyst sensitivity. The glassy carbon electrode modified with Pd-Ni-P ternary NPs, which behaves as an efficient nonenzymatic glucose sensor, offers excellent electrocatalytic performance with a high sensitivity of 1,136 μA·mM^-1·cm^-2, a short response time of 2 s, a wide linear range of 0.5 μM to 10.24 mM, a low limit of detection of 0.15 μM （signal-to-noise ratio = 3）, and good selectivity and reproducibility. Moreover, owing to its superior catalytic performance, the Pd-Ni-P modified electrode has excellent reliability for glucose detection in real samples of human serum. Our study provides a promising alternative strategy for designing and constructing high-performance multicomponent nanocatalyst-based sensors.
文摘The microstructure and solute distribution of Pd40Ni40P40 alloy solidified both on board a Chinese retrievable satellite (μg) and on the earth (1g) were studied. It was found that the dendritic primary phase formed under microgravity condition was finer and shorter. In the central area of the sample some asteroidal patterns of the primary phase were present in the microstructure. The primary spacing of the dendrites at the cooling rate of 0.056 K/s was smaller than that measured in the ground-based experiments at the same cooling rate, but almost the same as that cooled at 0.67 K/s on the ground. With these experimental results, mass transport coefficients both in space and on the earth were evaluated.
