Spectroscopic Determination of the Electrochemical Potentials of n-Type Doped Carbon Nanotubes
Spectroscopic Determination of the Electrochemical Potentials of n-Type Doped Carbon Nanotubes
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DOI：
10.1021/jp211583t
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发表时间：
2012-03-08
影响因子：
3.7
通讯作者：
Lee, Young Hee
中科院分区：
文献类型：
--
作者：
Kim, Soo Min;Kim, Ki Kang;Lee, Young Hee
了解涉及碳纳米管和化学吸附剂之间大量电荷转移的掺杂机制对于基础科学知识和纳米器件应用至关重要。然而，很难估计掺杂碳纳米管电子结构的改变。在这里，我们报告了使用光致发光（PL）测量对 n 掺杂单壁碳纳米管（SWCNT）的电化学势的测量。根据n型掺杂前后测量的PL强度的变化，利用Nernst方程提取电化学势。随着掺杂剂摩尔浓度的增加，测得的单壁碳纳米管的电化学电势接近单壁碳纳米管的理论还原电势。通过吸收光谱的变化也证实了掺杂效果。 PL 和吸收强度的猝灭与掺杂剂的标准还原电位及其浓度密切相关。这项研究可能成为太阳能电池、发光二极管和纳米发电机等基于单壁碳纳米管的电子设备应用的基石。
Understanding the doping mechanism that involves substantial charge transfer between carbon nanotubes and chemical adsorbent is of critical importance for both basic scientific knowledge and nanodevice applications. Nevertheless, it is difficult to estimate the modification of electronic structures of the doped carbon nanotubes. Here we report measurements of electrochemical potentials of n-doped single-walled carbon nanotubes (SWCNTs) by using photoluminescence (PL) measurement. The change of the measured PL intensity before and after n-type doping was used to extract the electrochemical potential using the Nernst equation. The measured electrochemical potentials of SWCNTs approached the theoretical reduction potential of SWCNTs as the mole concentration of the dopant increased. The doping effect was also confirmed by the change of absorption spectroscopy. The quenching of the PL and absorption intensity was strongly correlated to the standard reduction potential of the dopant and its concentration. This investigation could be a cornerstone for SWCNTs-based electronic device applications such as solar cells, light-emitting diodes, and nanogenerators.