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ACS Nano. 2013 Aug 27;7(8):6507-21. doi: 10.1021/nn402412t. Epub 2013 Jul 9.
The thermal oxidation of carbon nanotubes in air is investigated by in situ Raman spectroscopy. Etching rates are directly seen to be diameter, chirality, and type dependent. We directly track the evolution of bundled nanotube networks that undergo air etching from 300 to 600 °C. Some species are more robust than others. Changes to radial breathing mode (RBM) and G- peak structures suggest that metallic species etch away more rapidly, with smaller diameter semiconducting species etching more slowly and large diameter nanotubes, including semiconductors, etching last. The decay in integrated G and D band intensities is tracked and fit reasonably well with biexponential decay. The RBM evolution is better represented by a single exponential. All bands are fit to activation plots with RBMs showing significantly different rates.
采用原位拉曼光谱法研究了空气中碳纳米管的热氧化。发现刻蚀速率直接与直径、手性和类型有关。我们直接跟踪了在 300 到 600°C 下经历空气刻蚀的束状纳米管网络的演变。一些物种比其他物种更稳定。径向呼吸模式 (RBM) 和 G-峰结构的变化表明，金属物种的刻蚀速度更快，直径较小的半导体物种的刻蚀速度较慢，而包括半导体在内的大直径纳米管的刻蚀速度最慢。跟踪并合理拟合了积分 G 和 D 带强度的衰减，与双指数衰减拟合得相当好。RBM 的演化用单指数表示更好。所有的波段都拟合到活化图中，RBM 显示出明显不同的速率。
