98
5 Synthesis of Three-Dimensional Nanomaterials
Through a galvanostatic method, Zhang et al. electrochemically polymerized
polythiophene (PTh) onto the multiwalled carbon nanotube (MWCNT) modified
carbon paper in an oil-in-ionic liquid microemulsion (O/IL) (Zhang et al. 2014).
An O/IL microemulsion was prepared by dispersing an oil phase with reactants into
a continuous IL phase. It contains 1 mL n-hexane as the oil phase, where 0.3 mL
thiophene monomer was dissolved, 2.7 g TritonX-100 as the non-ionic surfactant
and 2 mL ionic liquids of (BMIM)PF6 as the continuous phase. After a moderate
stirring, a transparent and uniform O/IL microemulsion was formed. Polythiophene
was deposited on the multiwalled carbon nanotube in the prepared O/IL microemulsion by a galvanostatic procedure in a one-compartment cell with a two-electrode
configuration at the constant current of 3 mA. The MWCNT modified carbon paper
electrode of dimension (1 × 1 cm) was used as the working electrode, and a graphite
rod with a diameter of 6 mm was used as counter electrode. After polymerization,
PTh/MWCNT composite film was obtained after being washed with ethanol and
deionized water, and then dried in air. The neat polythiophene was deposited on
carbon paper in the same way to act as contrast tests for further characterization.
As-prepared PTh/MWCNT composites had an interlaced framework morphology, at
the same time, MWCNTs had been equably coated by PTh with thickness of 2–3 nm.
A novel, valid method has been researched for the fabrication of composites using
manganese oxide (MnO 2 ) grown in situ on 3D graphene through reverse microemulsion (water-in-oil) method (Wei et al. 2016). A uniform coating of nanoscale MnO 2
layers could be surveyed on internal surface of 3D graphene, which might be advantageous for rapid ionic and electronic transport. Those electrochemical properties of
MnO 2 /3D graphene composites are able to be optimized by controlling composite
structures and mass loading of MnO 2 . Similarly, MnO 2 /3D reduced graphene oxide
(RGO) composites had been reached through reverse microemulsion (water/oil)
method in Fig. 5.9 (Wei et al. 2015). Initially, the oil system was prepared by mixing
50 mL of cyclohexane (oil), 57.1 mL of isopropyl alcohol (cosurfactant), and 16.7 mL
of OP-10 (surfactant). The intermingled solution had been kept stirring through one
magnetic bar until it became transparent. 0.01 g of 3D RGO was joined in that solution, and then divided into two equal aliquots. Then, aqueous solutions of KMnO 4
(0.1 M) and MnSO 4 · H 2 O (0.15 M) were added into the two oil system aliquots,
respectively. Homogeneous reverse microemulsions (w/o) were prepared by stirring
for 5 min. The reverse microemulsion of KMnO 4 was then dropped into the system
containing MnSO 4 · H 2 O under stirring and the reverse microemulsion reaction was
carried out at a constant temperature of 28 °C for 14 h. The product (dark brown
precipitate) had been separated through centrifugation and washed with ethanol and
deionized water, which is in order to remove organic compounds and surfactant.
The MnO 2 /3D RGO composite was freeze dried for 48 h. MnO 2 nanoparticles (3–
20 nm in diameter) with diverse morphologies had been prepared and dispersed in
the same way on macropore surfaces of 3D RGO, providing channels for rapid ionic
and electronic transport.
Furthermore, hybrid supercapacitors (battery-supercapacitor hybrid devices,
HSCs) transfer high energy in seconds (excellent rate capability), along with
5 Synthesis of Three-Dimensional Nanomaterials
Through a galvanostatic method, Zhang et al. electrochemically polymerized
polythiophene (PTh) onto the multiwalled carbon nanotube (MWCNT) modified
carbon paper in an oil-in-ionic liquid microemulsion (O/IL) (Zhang et al. 2014).
An O/IL microemulsion was prepared by dispersing an oil phase with reactants into
a continuous IL phase. It contains 1 mL n-hexane as the oil phase, where 0.3 mL
thiophene monomer was dissolved, 2.7 g TritonX-100 as the non-ionic surfactant
and 2 mL ionic liquids of (BMIM)PF6 as the continuous phase. After a moderate
stirring, a transparent and uniform O/IL microemulsion was formed. Polythiophene
was deposited on the multiwalled carbon nanotube in the prepared O/IL microemulsion by a galvanostatic procedure in a one-compartment cell with a two-electrode
configuration at the constant current of 3 mA. The MWCNT modified carbon paper
electrode of dimension (1 × 1 cm) was used as the working electrode, and a graphite
rod with a diameter of 6 mm was used as counter electrode. After polymerization,
PTh/MWCNT composite film was obtained after being washed with ethanol and
deionized water, and then dried in air. The neat polythiophene was deposited on
carbon paper in the same way to act as contrast tests for further characterization.
As-prepared PTh/MWCNT composites had an interlaced framework morphology, at
the same time, MWCNTs had been equably coated by PTh with thickness of 2–3 nm.
A novel, valid method has been researched for the fabrication of composites using
manganese oxide (MnO 2 ) grown in situ on 3D graphene through reverse microemulsion (water-in-oil) method (Wei et al. 2016). A uniform coating of nanoscale MnO 2
layers could be surveyed on internal surface of 3D graphene, which might be advantageous for rapid ionic and electronic transport. Those electrochemical properties of
MnO 2 /3D graphene composites are able to be optimized by controlling composite
structures and mass loading of MnO 2 . Similarly, MnO 2 /3D reduced graphene oxide
(RGO) composites had been reached through reverse microemulsion (water/oil)
method in Fig. 5.9 (Wei et al. 2015). Initially, the oil system was prepared by mixing
50 mL of cyclohexane (oil), 57.1 mL of isopropyl alcohol (cosurfactant), and 16.7 mL
of OP-10 (surfactant). The intermingled solution had been kept stirring through one
magnetic bar until it became transparent. 0.01 g of 3D RGO was joined in that solution, and then divided into two equal aliquots. Then, aqueous solutions of KMnO 4
(0.1 M) and MnSO 4 · H 2 O (0.15 M) were added into the two oil system aliquots,
respectively. Homogeneous reverse microemulsions (w/o) were prepared by stirring
for 5 min. The reverse microemulsion of KMnO 4 was then dropped into the system
containing MnSO 4 · H 2 O under stirring and the reverse microemulsion reaction was
carried out at a constant temperature of 28 °C for 14 h. The product (dark brown
precipitate) had been separated through centrifugation and washed with ethanol and
deionized water, which is in order to remove organic compounds and surfactant.
The MnO 2 /3D RGO composite was freeze dried for 48 h. MnO 2 nanoparticles (3–
20 nm in diameter) with diverse morphologies had been prepared and dispersed in
the same way on macropore surfaces of 3D RGO, providing channels for rapid ionic
and electronic transport.
Furthermore, hybrid supercapacitors (battery-supercapacitor hybrid devices,
HSCs) transfer high energy in seconds (excellent rate capability), along with