Preparation and characterization of a composite hydrogel with graphene oxide as an acid catalystElectronic supplementary information (ESI) available: Formation mechanism of PF; SEM images of GO and PF; comparison of the polymerization process of pyrrole and three different aldehydes in water and HCl; TEM images of GOP-1 and GO; IR spectra of GO, GOP-1 and PF. See DOI: 10.1039/c5sm00142k

• Main Authors: Jiang, Ting, Sui, Zhu-Yin, Yang, Quan-Sheng, Zhang, Xuetong, Han, Bao-Hang
• Format: Article
• Language: English
• ISSN: 1744-683X; 1744-6848
• DOI: 10.1039/c5sm00142k

In this study, a facile method for synthesizing a novel graphene oxide/pyrrole-formaldehyde (GOP-1) composite hydrogel was developed via in situ polymerization of pyrrole and formaldehyde in the presence of graphene oxide sheets without any additional catalyst. During the polymerization, graphene oxide can act as a two-dimensional template to regulate the aggregation state of polymer and as an acid catalyst to accelerate the reaction rate of pyrrole and formaldehyde. The morphology and microstructure were investigated by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction, respectively. The chemical properties were analyzed via X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. The freeze-dried GOP-1 composite hydrogel exhibited a large specific surface area, high nitrogen content, and three-dimensional network structure. Based on the above features, the freeze-dried GOP-1 composite hydrogel used as a gas adsorbent showed a high carbon dioxide uptake capacity at 1.0 bar and 273 K (11.1 wt%), in sharp contrast to that of graphene oxide (7.4 wt%). Furthermore, the as-prepared composite hydrogel may possess attractive potential in the fields of electrode material, tissue engineering, and water treatment. A homogeneous composite hydrogel was prepared via in situ polymerization of pyrrole and formaldehyde in the presence of GO sheets.