Surface Modification of Textiles with Nanomaterials …
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equal and opposite charge density present in the inner surface of the triboelectric
layers
2. This separation of triboelectric layers results in the electrons being driven to the
electrode to equalize the potential drop created
Commonly used dielectric materials to attain higher tendency to gain or lose
electrons for triboelectric applications are given in Table 1.
TENGs have four different types of operational modes as proposed by Zhong
et al. [113] as given below:
• “Vertical contact separation mode
• Lateral sliding mode
• Single electrode mode
• Free standing triboelectric layer mode”
I. Vertical Contact Separation Mode [113]
The vertical contact separation mode of a triboelectric nanogenerator reported by
Wang and Zhu [113] is shown in Fig. 11a. Here, two dissimilar dielectric materials
are made to face each other, where the surfaces (top and bottom) of dielectric materials
were deposited with copper for contact establishment by physical vapour deposition
techniques like sputtering, thermal vapour deposition, pulsed laser deposition and
so on [114]. The physical contact between the two dielectric layers promotes the
development of oppositely charged surfaces on the materials. Potential drop is created
when external kinetic energy is supplied to separate the two thin sheets. If the two
electrodes are electrically coupled with an external load, the generated free electrons
in one electrode terminal will try to flow to another electrode, to equalize this potential
drop. Once the separation between the dielectric layers is padlocked, the created
charges get vanished, and electrons flow back to the same electrode [115].
II. Lateral Sliding Mode [113]
Wang and Zhu [113] developed this mode and is shown in Fig. 11b. In this mode,
relative sliding of the two dissimilar dielectric layers leads to polarization of the
surface in-turn charge transport happens towards the oppositely charged electrodes
to equalize the created electrostatic field by the triboelectric charges. In addition,
periodic sliding can produce AC power as output. This mode of operation is called a
sliding mode. TENG. Jing [116] and Lin [117] stated that the sliding can be carried
out either in cylindrical rotation, disk rotation or planar motion.
III. Single-electrode Mode [113]
From the above two modes, physical contacts were established by connecting an
intermediate load, which promoted the TENGs to move freely and have mobile
portability. Though the TENGs have excellent portability, it cannot be electrically
connected to the load due to its mobile object (i.e., man lifting an object). To overcome
the issues from the previous modes and to harvest energy, a single-electrode mode
TENG was proposed. In this mode, an electrode on the bottom side of the dielectric
layer of the TENG is grounded and it is shown in Fig. 11c. In particular, the size of the
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equal and opposite charge density present in the inner surface of the triboelectric
layers
2. This separation of triboelectric layers results in the electrons being driven to the
electrode to equalize the potential drop created
Commonly used dielectric materials to attain higher tendency to gain or lose
electrons for triboelectric applications are given in Table 1.
TENGs have four different types of operational modes as proposed by Zhong
et al. [113] as given below:
• “Vertical contact separation mode
• Lateral sliding mode
• Single electrode mode
• Free standing triboelectric layer mode”
I. Vertical Contact Separation Mode [113]
The vertical contact separation mode of a triboelectric nanogenerator reported by
Wang and Zhu [113] is shown in Fig. 11a. Here, two dissimilar dielectric materials
are made to face each other, where the surfaces (top and bottom) of dielectric materials
were deposited with copper for contact establishment by physical vapour deposition
techniques like sputtering, thermal vapour deposition, pulsed laser deposition and
so on [114]. The physical contact between the two dielectric layers promotes the
development of oppositely charged surfaces on the materials. Potential drop is created
when external kinetic energy is supplied to separate the two thin sheets. If the two
electrodes are electrically coupled with an external load, the generated free electrons
in one electrode terminal will try to flow to another electrode, to equalize this potential
drop. Once the separation between the dielectric layers is padlocked, the created
charges get vanished, and electrons flow back to the same electrode [115].
II. Lateral Sliding Mode [113]
Wang and Zhu [113] developed this mode and is shown in Fig. 11b. In this mode,
relative sliding of the two dissimilar dielectric layers leads to polarization of the
surface in-turn charge transport happens towards the oppositely charged electrodes
to equalize the created electrostatic field by the triboelectric charges. In addition,
periodic sliding can produce AC power as output. This mode of operation is called a
sliding mode. TENG. Jing [116] and Lin [117] stated that the sliding can be carried
out either in cylindrical rotation, disk rotation or planar motion.
III. Single-electrode Mode [113]
From the above two modes, physical contacts were established by connecting an
intermediate load, which promoted the TENGs to move freely and have mobile
portability. Though the TENGs have excellent portability, it cannot be electrically
connected to the load due to its mobile object (i.e., man lifting an object). To overcome
the issues from the previous modes and to harvest energy, a single-electrode mode
TENG was proposed. In this mode, an electrode on the bottom side of the dielectric
layer of the TENG is grounded and it is shown in Fig. 11c. In particular, the size of the