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Electrodes modified with 3D graphene composites: a review on methods for preparation, properties and sensing applications

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Nadeem Baig
Nadeem Baig
Nadeem Baig
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Tawfik A. Saleh
Tawfik A. Saleh
Tawfik A. Saleh
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Abstract and Figures

Three-dimensional (3D) porous networks of planar 2D graphene have attractive features with respect to sensing. These include a large electroactive surface area, good inner and outer surface contact with the analyte, ease of loading with (bio)catalysts, and good electrochemical sensitivity. 3D free-standing graphene can even be used directly as an electrode. This review (with 140 refs.) covers the progress made in the past years. Following an introduction into the field (including definitions), a large section is presented that covers methods for the synthesis of 3D graphene (3DG) (including chemical vapor deposition, hydrothermal methods, lithography, support assisted synthesis and chemical deposition, and direct electrochemical methods). The next section covers the key features of 3DG and its composites for use in electrochemical sensors. This section is subdivided into sections on the uses of 3D porous graphene, 3DG composites with metals and metal oxides, composites consisting of 3DG and organic polymers, and electrodes modified with 3DG, 3DGs decorated with carbon nanotubes, and others. The review concludes with a discussion of future perspectives and current challenges. Graphical AbstractA schematic of the key characteristics of three-dimensional (3D) graphene
a Photographs of a 2 mg/mL homogeneous GO aqueous dispersion before and after hydrothermal reduction at 180 °C for 12 h; b photographs of a strong SGH allowing easy handling and supporting weight; c–e SEM images with different magnifications of the SGH interior microstructures; f room temperature I–V curve of the SGH exhibiting Ohmic characteristic, inset shows the two-probe method for the conductivity measurements [72]. Copyright (2010) American Chemical Society
a Photographs of a 2 mg/mL homogeneous GO aqueous dispersion before and after hydrothermal reduction at 180 °C for 12 h; b photographs of a strong SGH allowing easy handling and supporting weight; c–e SEM images with different magnifications of the SGH interior microstructures; f room temperature I–V curve of the SGH exhibiting Ohmic characteristic, inset shows the two-probe method for the conductivity measurements [72]. Copyright (2010) American Chemical Society
… 
SEM images of the lithographically generated porous carbon (a), porous carbon coated with nickel before thermal annealing (b), and 3D graphene structure after annealing at 750 C° and etching of Ni layer in a 2 M H2SO4 solution (c, d) [76]. Copyright (2012) American Chemical Society
SEM images of the lithographically generated porous carbon (a), porous carbon coated with nickel before thermal annealing (b), and 3D graphene structure after annealing at 750 C° and etching of Ni layer in a 2 M H2SO4 solution (c, d) [76]. Copyright (2012) American Chemical Society
… 
Schematic drawings illustrating the steps and mechanism for chemical conversion of amorphous porous carbon to 3D graphene: a porous carbon, b conformal Ni coating, c diffusion of carbon into Ni top surface during thermal annealing, and d hollow 3D graphene after Ni etching [76]. Copyright (2012) American Chemical Society
Schematic drawings illustrating the steps and mechanism for chemical conversion of amorphous porous carbon to 3D graphene: a porous carbon, b conformal Ni coating, c diffusion of carbon into Ni top surface during thermal annealing, and d hollow 3D graphene after Ni etching [76]. Copyright (2012) American Chemical Society
… 
The illustration of the fabrication procedure of the graphene–PANI hollow spheres (RGO-PANI HS). In the first step, the PANI wrapped PS sphere was formed by mixing negatively charged PS sphered with positively charged PANI. In the second step, the negatively charged RGO sheets self-assembled on PANI@PS by dipping PANI@PS into RGO dispersion. The first and second steps are multiple times repeated to produce (RGO–PANI)n@PS. In the final step, the PS core was removed by dipping in tetrahydrofuran (THF) to generate RGO-PANI HS [83]. Copyright (2015) Elsevier Ltd.
The illustration of the fabrication procedure of the graphene–PANI hollow spheres (RGO-PANI HS). In the first step, the PANI wrapped PS sphere was formed by mixing negatively charged PS sphered with positively charged PANI. In the second step, the negatively charged RGO sheets self-assembled on PANI@PS by dipping PANI@PS into RGO dispersion. The first and second steps are multiple times repeated to produce (RGO–PANI)n@PS. In the final step, the PS core was removed by dipping in tetrahydrofuran (THF) to generate RGO-PANI HS [83]. Copyright (2015) Elsevier Ltd.
… 
SEM images the surface of ErGO modified electrode with different magnifications, respectively [88]. Copyright (2013) Elsevier Ltd.
+4
SEM images the surface of ErGO modified electrode with different magnifications, respectively [88]. Copyright (2013) Elsevier Ltd.
… 
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REVIEW ARTICLE
Electrodes modified with 3D graphene composites: a review on methods
for preparation, properties and sensing applications
Nadeem Baig
1
&Tawfik A. Saleh
1
Received: 4 February 2018 /Accepted: 14 April 2018 /Published online: 7 May 2018
#Springer-Verlag GmbH Austria, part of Springer Nature 2018
Abstract
Three-dimensional (3D) porous networks of planar 2D graphene have attractive features with respect to sensing. These include a
large electroactive surface area, good inner and outer surface contact with the analyte, ease of loading with (bio)catalysts, and
good electrochemical sensitivity. 3D free-standing graphene can even be used directly as an electrode. This review (with 140
refs.) covers the progress made in the past years. Following an introduction into the field (including definitions), a large section is
presented that covers methods for the synthesis of 3D graphene (3DG) (including chemical vapor deposition, hydrothermal
methods, lithography, support assisted synthesis and chemical deposition, and direct electrochemical methods). The next section
covers the key features of 3DG and its composites for use in electrochemical sensors. This section is subdivided into sections on
the uses of 3D porous graphene, 3DG composites with metals and metal oxides, composites consisting of 3DG and organic
polymers, and electrodes modified with 3DG, 3DGs decorated with carbon nanotubes, and others. The review concludes with a
discussion of future perspectives and current challenges.
Keywords Porous carbon .Three-dimensional material .Quantum dots .Lithography .Hydrothermal synthesis .Chemical vapor
deposition .3D printing .Electrochemical sensor .Biosensor .Conductive polymer .Nanoparticles
Introduction
Graphene consists of a single layer of sp
2
hybridized carbon
atoms arranged in a honeycomb-like lattice [1]. Graphene has
made its way into different fields of research including
photocatalysis, batteries, electrochemical sensors and biosen-
sors, gas sensors, and supercapacitors [2,3]. Graphene is an
interesting two-dimensional (2D) planar material which can
be rolled into one-dimensional (1D) nanotubes, wrapped into
zero-dimensional (0D) fullerenes. The sheets stacking result
in the formation of three-dimensional (3D) graphite [1,4].
Graphene displays amazing exceptional characteristics. It is
the known thinnest material in the universe and the strongest
ever measured material [5]. It is transparent with incredible
flexibility [6]. Its optical transparency is ∼97.3% [7,8].
Graphene mechanical strength is 200 times superior to steel
[9]. Graphene has an exceptionally high theoretical surface
area (2630 m
2
g
−1
) which is substantially huge compared to
graphite (∼10 m
2
g
−1
) and two times larger than the carbon
nanotubes (1315 m
2
g
−1
)[10]. Graphene displayed the ultra-
high electron mobility 200,000 cm
2
V
−1
s
−1
with charge den-
sity ∼2×10
11
cm
−2
[10–12]. Graphene possessed extraordi-
nary thermal conductivity of 3000 WmK
−1
[13,14]
.
It is ob-
vious that electrode materials perform a critical role in the
fabrication of high-performance electrochemical sensor [15].
These unique and extraordinary physicochemical properties
solidify the role of graphene in the field of material science
and forthcoming technology.
Materials that are closely related to graphene are sometimes
referred to as graphene. In some applications, both
graphene oxide (GO) and reduced graphene oxide (rGO) also
have been denoted as graphene. However, the pristine
graphene has some obvious differences from GO and rGO.
Graphene is a 2D material which only contains sp
2
hybridized
carbon atoms, whereas GO is a monolayer of graphite oxide.
GO contains both sp
2
and sp
3
carbon atoms. The sp
3
bonding
in GO is around 40% [16]. It also has many oxygen-
containing functional groups. The hydroxy and the epoxy
groups are present on the basal plane and the sheet edges of
the GO contain phenol, quinone, lactone, carbonyl, and
*Nadeem Baig
nadeembaig@kfupm.edu.sa; nadeembaig38@gmail.com
1
Chemistry Department, King Fahd University of Petroleum and
Minerals, Dhahran 31261, Saudi Arabia
Microchimica Acta (2018) 185: 283
https://doi.org/10.1007/s00604-018-2809-3
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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