Hydrogen Energy Storage Materials Based on Conducting Polymers and Their Nanocomposites

摘要

Novel hydrogen energy storage materials based on electrically conducting polymers and their nanocompistes are reported. The synthesis and hydrogen adsorption properties of polypyrrole and its composites with nanotubes were investigated. The prepared polypyrrole has been characterized by scanning electron microscopy, thermogravimeteric analysis, and FTIR spectroscopy. In addition, the nitrogen adsorption-desorption was measured and the hydrogen adsorption capacity was measured volumetrically by the computer-controlled commercial "pressure-composition temperature". The as-prepared mesoporous polypyrrole has been found to reversibly adsorb 2.2 wt% H_2 at 77 K and 9 MPa. The composites were synthesized by a facile and environmentally friendly method, wherein pyrrole was polymerized on the surfaces of the halloysite nanotubes via a solid-state, vapor-phase polymerization technique. In this manner, the polypyrrole was not only polymerized on the external surfaces of the halloysite nanotubes but was also intercalated between the halloysite nanotubes layers. The halloysite nanotube-polypyrrole composite materials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), electrical conductivity measurements, FTIR spectroscopy and a pressure-composition temperature (PCT) apparatus. The hydrogen storage capacity of the new composite was enhanced by 21% in comparison to pristine nanotubes.