Deborah M, Jawahar A, Mathavan T, Kumara Dhas M, Benial A Milton Franklin
Department of Chemistry, NMSSVN College, Madurai 625 019, Tamil Nadu, India.
Department of Physics, NMSSVN College, Madurai 625 019, Tamil Nadu, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Oct 22. doi: 10.1016/j.saa.2014.09.065.
Single-walled carbon nanotubes (SWCNTs) have a great potential in a wide range of applications, but faces limitation in terms of dispersion feasibility. The functionalization process of SWCNTs with the amino acid, glycine involves oxidation reaction using a mild aqueous acid mixture of HNO and HSO (1:3), via ultrasonication technique and the resulted oxidized SWCNTs were again treated with the amino acid glycine suspension. The resulted glycine functionalized carbon nanotubes have been characterized by XRD, UV-Vis, FTIR, EPR, SEM, and EDX, spectroscopic techniques. The enhanced XRD peak (002) intensity was observed for glycine functionalized SWCNTs compared with oxidized SWCNTs, which is likely due to sample purification by acid washing. The red shift was observed in the UV-Vis spectra of glycine functionalized SWCNTs, which reveals that the covalent bond formation between glycine molecule and SWCNTs. The functional groups of oxidized SWCNTs and glycine functionalized SWCNTs were identified and assigned. EPR results indicate that the unpaired electron undergoes reduction process in glycine functionalized SWCNTs. SEM images show that the increase in the diameter of the SWCNTs was observed for glycine functionalized SWCNTs, which indicates that the adsorption of glycine molecule on the sidewalls of oxidized SWCNTs. EDX elemental micro analysis confirms that the nitrogen element exists in glycine functionalized SWCNTs. The functionalization has been chosen due to CONH bioactive sites in glycine functionalized SWCNTs for future applications.
单壁碳纳米管（SWCNTs）在广泛的应用中具有巨大潜力，但在分散可行性方面面临限制。用氨基酸甘氨酸对SWCNTs进行功能化处理的过程包括使用温和的硝酸和硫酸（1:3）水溶液混合物通过超声技术进行氧化反应，然后将所得的氧化SWCNTs再次用氨基酸甘氨酸悬浮液处理。所得的甘氨酸功能化碳纳米管已通过XRD、UV-Vis、FTIR、EPR、SEM和EDX等光谱技术进行了表征。与氧化的SWCNTs相比，甘氨酸功能化的SWCNTs的XRD峰（002）强度增强，这可能是由于酸洗对样品进行了纯化。在甘氨酸功能化的SWCNTs的UV-Vis光谱中观察到红移，这表明甘氨酸分子与SWCNTs之间形成了共价键。对氧化的SWCNTs和甘氨酸功能化的SWCNTs的官能团进行了鉴定和归属。EPR结果表明，在甘氨酸功能化的SWCNTs中未成对电子经历了还原过程。SEM图像显示，甘氨酸功能化的SWCNTs的SWCNTs直径增加，这表明甘氨酸分子吸附在氧化的SWCNTs的侧壁上。EDX元素微分析证实甘氨酸功能化的SWCNTs中存在氮元素。由于甘氨酸功能化的SWCNTs中的CONH生物活性位点，选择了这种功能化用于未来的应用。
