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Photoconductivity of Single-crystalline Selenium Nanotubes

Peng Liu·Yurong Ma·Weiwei Cai·Zhenzhong Wang·Limin Qi·Dongmin Chen
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Abstract

Photoconductivity of single-crystalline selenium nanotubes (SCSNT) under a range of illumination intensities of a 633nm laser is carried out with a novel two terminal device arrangement at room temperature. It's found that SCSNT forms Schottky barriers with the W and Au contacts, and the barrier height is a function of the light intensities. In low illumination regime below 1.46x10E-4 muWmum-2, the Au-Se-W hybrid structure exhibits sharp switch on/off behavior, and the turn-on voltages decrease with increasing illuminating intensities. In the high illumination regime above 7x10E-4 muWmum-2, the device exhibits ohmic conductance with a photoconductivity as high as 0.59Ohmcm-1, significantly higher that reported values for carbon and GaN nanotubes. This finding suggests that SCSNT is potentially a good photo-sensor material as well we a very effective solar cell material.

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Peng Liu, Yurong Ma, Weiwei Cai, Zhenzhong Wang, Limin Qi, Dongmin Chen. 2007-02-05. Photoconductivity of Single-crystalline Selenium Nanotubes. https://doi.org/10.1088/0957-4484%2F18%2F20%2F205704

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