ELECTROCHEMICAL CONTORL OF SIGLE ELECTRON TRANSFER AT INTERFACES IN SOLUTION

银纳米粒子(d=约20 nm)吸附在浸泡在纯水中的玻璃板表面，在外加电场的白光照射下溶解。通过吸收光谱的变化来监测溶出度。结构表征表明，由于处理的结果，玻璃上的银纳米颗粒数量减少。然而，经过处理后，颗粒的尺寸增加到约80纳米。结构的变化率取决于照射的光强度和外部电场的存在。结果表明，光激发与溶液中银纳米粒子的极化作用相结合，导致吸附在玻璃板上的银纳米粒子的结构发生了变化。这种变化归因于金属在银纳米颗粒表面的高度局域电化学反应。通过电化学腐蚀或沉积的方法，在可持续的细金丝的间隙成功地在溶液中制备了铜、银、镍、钯和铅的金属纳米接触。在铜、银、镍和钯的接触处，表现出单位值的相对稳定的电导量子化行为明显。与其他金属相比，铅触头的电导量子化行为相当不稳定。首次在室温下观察到溶液中Ni、Pd和Pd纳米接触的电导量子化。

Ag nanoparticles(d = ca. 20 nm) adsorbed on the surface of a glass plate immersed in pure water dissolved when white light was irradiated under application of an external electric field. Dissolution was monitored via change in absorption spectrum. Structural characterization revealed that the number of Ag nanoparticles on the glass decreased as a consequence of the treatment. The size of the particles, however, increased to ca. 80 nm following the treatment. The rate of change in the structure was dependent on both the irradiated light intensity and the existence of an external electric field. The results demonstrate that photo-excitation combined with the electric polarization of Ag nanoparticles in solution leads to structural changes in Ag nanoparticles adsorbed on a glass plate. The changes were attributable to the highly localized electrochemical reactions of metal dissolution/deposition on the surface of the Ag nanoparticles.Metal nano-contacts of Cu, Ag, Ni, Pd and Pb were successfully fabricated via the electrochemical etching or deposition method at a gap of a sustainable thin gold wire in solution. Relatively stable behaviors of the conductance quantization exhibiting a unit value were apparent at the contacts of Cu, Ag, Ni, and Pd. Conductance quantization behavior of the Pb contact was rather unstable in comparison with other metals. The conductance quantization of Ni, Pd and Pb nano-contacts in solution at room temperature was observed for the first time in the present system.