Chemically Grafted Aminated Carbon Nanotubes and l-Lysine in Ultramodified Conditions for Carbon Dioxide Storage

The study reported CO2 storage properties of single-walled carbon nanotubes (CNTs) modified by introducing amino groups onto CNT surfaces via a chemical process. Two different approaches were used to produce amino-functionalized nanotubes by adding lithium amide and l-lysine amino acid. Lithium amide was introduced on CNT surfaces, and then, it was further modified by adding amino-moiety (l-lysine amino acid) to obtain multiamino sites on the CNT surface for CO2 storage. The aminated CNT were followed by CO2 adsorption experiments, and amino group interactions with CO2 have helped CNT to achieve higher adsorption capacity. The successful modification of CNTs showed ameliorated CO2 storage capacity as compared to pristine CNT. The modified CNT possessed free amine groups on the surface, which led to an enhanced CO2 adsorption capacity. The modified CNT samples were analyzed by X-ray photoelectron spectroscopy, infrared spectroscopy, and X-ray diffraction techniques.