Environmental Engineering Reference
In-Depth Information
4
Multifunctional nanocoMposites
for environMental reMediation
Suying Wei
1
, Jiahua Zhu
1,2
, Hongbo Gu
2
, Huige Wei
2
, Xingru Yan
2
, Yudong Huang
3
,
and Zhanhu Guo
2
1
Department of Chemistry and Biochemistry, Lamar University, Beaumont, TX, USA
2
Integrated Composites Laboratory (ICL), Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX, USA
3
School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin, Heilongjiang, China
4.1
introduction
Nanocomposites are materials that are composed of more than two components with at least one in the nanoscale (1-100 nm)
range. The central theme of making nanocomposites is to integrate nanomaterials with others into one entity, thus generating
so-called synergistic properties and/or performances. Multifunctional nanocomposites are an excellent illustration of targeting
nanocomposites, in which each of the components is structure- and property-integrated uniquely to produce hybrid materials
that possess multifunctionalities in both structure and properties. Reflecting the authors' research interests and experiences, in
this chapter we mainly focus on polymer-based and carbon-based multifunctional nanocomposites. Polymers have been con-
sidered as excellent host matrices for nanocomposite materials. They have been extensively investigated for their potential wide
applications because of their easy processability, low-cost manufacturing, good adhesion to substrates, and unique physico-
chemical properties. Polymer nanocomposites (PNCs) are polymer composites using nanostructured materials as fillers.
Depending on the type of filler material, different properties can be achieved for PNCs. The types of polymer matrices, insu-
lating or conducting, also render the nanocomposites with significantly different synergy. Carbon-based structures as another
type of matrix for nanocomposites may include carbon nanotubes, carbon nanofibers (NFs), carbon nanoplatelets, and gra-
phenes. The unique and interesting chemical and electronic structures of carbon have rendered carbon-based nanocomposites a
variety of noteworthy applications, including anticorrosion in electronic devices and sensors, environmental remediation for
heavy metals and other toxic species, and magnetic data storage and magnetic imaging.
Owing to the inherent synergistic properties of multifunctional nanocomposites, including electronic, optical, magnetic, and
mechanical, they have seen wide applications spanning the broad areas of electronics, energy, space, and biomedicine. For
example, magnetic PNCs that generally consist of magnetic nanofillers have shown great potential in high-density magnetic
recording, magnetic sensors, magnetic carriers, magnetic storage, and color imaging [1-4]. Multifunctional nanocomposites
have also found applications in electrochemical energy storage especially for developing Faradic supercapacitors (FS), which
currently suffer from low power density due to the slow faradic process during charge/discharge and poor cycling stability as a
result of the redox reaction that takes place on the electrode [5-7]. Multifunctional nanocomposites may comprise pseudoactive
materials (large faradic capacitance) such as metal oxide [8, 9] or conductive polymer nanostructures [10, 11] in a carbon matrix
(high conductivity and large specific surface area); thus it can potentially enhance the capacitance of the resulting composite
electrodes. For example, flexible polyaniline (PANI) film/graphene composite paper was produced via an in situ anodic elec-
tropolymerization process, and this material generated a capacitance of 233 F/g [12]. Furthermore, PANI nanowire arrays [13]
