Environmental Engineering Reference
In-Depth Information
34
Graphene: Applications in Environmental
Remediati
on and Sensing
Theruvakkattil Sreenivasan Sreeprasad
Department of Chemical Engineering, Kansas State University, Manhattan, Kansas, USA
CONTENTS
34.1 Graphene for Environmental Remediation .................................................................... 682
34.1.1 Graphene as an Adsorbent ................................................................................... 682
34.1.2 Graphene-Based Membranes ............................................................................... 689
34.1.3 Capacitive Deionization ........................................................................................ 691
34.1.4 Photocatalytic Removal ......................................................................................... 692
34.1.5 Graphene-Based Catalyst for Other Catalytic Degradation Methods............ 695
34.1.6 Antibacterial Properties of Graphene ................................................................. 695
34.2 Graphene-Based Contaminant Sensing Strategies ....................................................... 697
34.2.1 Graphene-Based FET Sensors .............................................................................. 697
34.2.2 Electrochemical Sensors ....................................................................................... 700
34.2.2.1 Graphene-Based Electrodes for Voltammetric and
Amperometric Sensors ........................................................................... 700
34.2.2.2 Potentiometric Sensors ........................................................................... 701
34.2.3 Colorimetric Sensors Based on Luminescence .................................................. 704
34.2.4 Graphene as SPE Material in Chromatographic Sensors ................................. 705
34.2.5 Surface-Enhanced Raman Spectroscopy-Based Sensors ................................. 706
34.3 New Directions .................................................................................................................. 707
34.4 Conclusions and Future Prospects .................................................................................. 708
References ..................................................................................................................................... 709
Graphene, a single atom-thick two-dimensional (2-D) sheet of hexagonal carbon matrix,
1
is
the newest member of the nanocarbon family and can be considered as the building block
for other carbon-based nanomaterials, such as fullerenes and carbon nanotubes (CNTs).
Graphenes possess a number of special properties that give them precedence over other
carbon allotropes. For example, the band structure of graphene is unique and it behaves as
a semimetal with zero band gap because the conduction band and the valence band come
in contact with each other at two points (K and K′) in the Brillouin zone.
2-4
Graphene also
has several other features such as highest room temperature mobility,
5-7
high quantum
capacitance,
8
exceptional electrical (~2000 S/cm) and thermal (5300 W/mK) conductivities,
9
transparency to visible light,
10
and exceptional mechanical strength (Young's modulus,
681
