Department of Physics and Key Laboratory of Atomic and Molecular Nanoscience of Education Ministry, Tsinghua University, Beijing, People's Republic of China.
Nanotechnology. 2011 Jan 21;22(3):035202. doi: 10.1088/0957-4484/22/3/035202. Epub 2010 Dec 9.
Macroscopically long core/shell structured Ag/Ag(2)S coaxial nanowires and Ag(2)S nanowires have been fabricated using the solid-state ionics method for Ag nanowires, combined with a subsequent gas-solid reaction, and characterized at different spatial scales. The photoconductive properties of such samples are investigated by performing transport measurements with 532 nm laser illumination ON/OFF cycles under different bias. A significant change in the photoconductivity from negative to positive has been observed in the coaxial structured Ag/Ag(2)S nanowires when the Ag(2)S layer thickness increases to a certain level. Such behaviors are ascribed to two photoconductive mechanisms in the Ag core and the Ag(2)S shell, respectively. These results indicate a promising approach to fabricate nanoscale photoswitches with different dark resistances and photoinduced currents based on the Ag/Ag(2)S coaxial nanowires for various optoelectronic applications.
采用固态离子学方法制备了 Ag 纳米线，并结合后续的气固反应，制备出了宏观长核/壳结构的 Ag/Ag2S 同轴纳米线和 Ag2S 纳米线，并在不同的空间尺度上对其进行了表征。通过在不同偏压下进行 532nm 激光照射 ON/OFF 循环的输运测量，研究了这些样品的光电导性能。当 Ag2S 层厚度增加到一定水平时，在同轴结构的 Ag/Ag2S 纳米线中观察到光电导从负到正的显著变化。这种行为归因于 Ag 核和 Ag2S 壳中的两种光电导机制。这些结果表明，基于 Ag/Ag2S 同轴纳米线，为各种光电应用，通过制备不同暗电阻和光电流的纳米级光开关，提供了一种很有前途的方法。
