U.S. Army Engineer Research and Development Center, U.S. Army Corps of Engineers, 3909 Halls Ferry Road, Building 3270, Vicksburg, MS, 39180, USA.
Bull Environ Contam Toxicol. 2020 Apr;104(4):455-463. doi: 10.1007/s00128-020-02811-2. Epub 2020 Feb 27.
Carbon nanotubes (CNTs) have unique properties which can be modified through surface functionalization. The ability of several functionalized and un-functionalized CNTs to bind copper was investigated as a first step toward developing a printable CNT-based sensor to detect copper in aqueous systems. Binding capacity and specificity were shown to vary by functionalization and vendor. CNTs from two vendors were tested, and the equilibrium binding data was fitted using two isotherm models. Calculated q (mg/g) values indicated one vendor's carboxyl-functionalized CNTs had the greatest binding capacity (94-115 mg/g), while other carboxyl-functionalized CNTs and amine-functionalized CNTs had similar capacities to un-functionalized CNTs (15-30 mg/g). Hydroxyl-functionalized CNTs had the lowest copper binding capacity (7-8 mg/g) of the CNTs tested. Freundlich isotherms showed no obvious trends in binding affinity, but suggested that binding was primarily due to chemisorption. Variations in CNT size, functionalization percentage, and purity could explain, partially, the observed adsorption differences.
碳纳米管 (CNTs) 具有独特的性质，可以通过表面功能化进行修饰。本研究通过考察几种功能化和非功能化 CNT 对铜的结合能力，以期开发出一种可用于检测水相体系中铜的基于 CNT 的可打印传感器。结果表明，结合能力和特异性因功能化和供应商而异。本研究测试了来自两个供应商的 CNT，并用两种等温线模型拟合平衡结合数据。计算的 q（mg/g）值表明，一个供应商的羧基功能化 CNT 具有最大的结合能力（94-115 mg/g），而其他羧基功能化 CNT 和胺功能化 CNT 与非功能化 CNT 的结合能力相似（15-30 mg/g）。羟基功能化 CNT 的铜结合能力最低（7-8 mg/g）。弗伦德利希等温线没有显示出明显的结合亲和力趋势，但表明结合主要是由于化学吸附。CNT 尺寸、功能化百分比和纯度的变化可以部分解释观察到的吸附差异。
