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D. K. Subbiah et al.
Active smart textiles: These materials react upon sensing a change in the surroundings
or a perturbation. They are equipped with actuators in conjunction with sensors and
take pre-determined actions.
Passive smart textiles: These are materials that can only sense a change in the
surrounding environment or any stimuli given to them.
Ultra-smart textiles: These materials possess the ability to adapt themselves to an
environmental perturbation or any variation in the signals that they receive. Mainly,
they consist of a central processing unit that acts as a brain having the requisite
predefined programs in place.
Nanoengineered textiles have been designed with a specific modality such as UV
blocking, conductivity, antibacterial properties, hydrophobicity, antistatic behaviour,
energy storage, chromic and sensing properties. This chapter highlights the field of
wearable electronics applications on textiles platform in great focus.
4.1 Smart Textiles for Energy Harvesting and Storage
Energy has been essential to human life and the energy requirement issues in present
times have been a major concern. Smart fabrics have emerged as one of the most
promising platforms to address energy harvesting and storage applications. Based on
this motivation, Wang et al. invented the piezoelectric [107] and triboelectric [108]
nanogenerators in 2006 and 2012 respectively. Our surrounding environment has
abundance in energies including wave, wind, droplet, thermal, chemical and other
mechanical forms. By utilizing the most abundant energies, triboelectric nanogenerators (TENGs) can effectively convert mechanical energy into electrical energy [109],
which facilitates contact electrification and electrostatic induction [109]. Generally,
daily activities of human beings, such as arm movement or footstep of a 65 kg adult
can generate approximately ~67 W of kinetic power [110]. In this context, nanostructured textiles provide a more effective way of approach to scavenge the energy
from human motion. Zhong et al. [111] introduced the first textile based triboelectric nanogenerators. The procedure proposed and developed by Zhong et al. [112]
has been described below: Generally, TENG comprises of four parts that includes
an electrode, positive and negative triboelectric layers, and supporting structures
(substrates, wires, spacers and power management systems, to name a few). The
two dissimilar triboelectric surfaces consist high electron affinity, so that it becomes
the negatively charged triboelectric layer and another layer comprises of positively
charged triboelectric layer. As a result of mechanical friction between the two dissimilar triboelectric layers, electrostatic charges were created and these charges lead
to the development of potential when they are separated by mechanical forces.
The working mechanism behind textile based TENGs is as follows:
1. During the contact establishment between two dissimilar materials under the
tension of mechanical force results in the production of electrical energy due to the
D. K. Subbiah et al.
Active smart textiles: These materials react upon sensing a change in the surroundings
or a perturbation. They are equipped with actuators in conjunction with sensors and
take pre-determined actions.
Passive smart textiles: These are materials that can only sense a change in the
surrounding environment or any stimuli given to them.
Ultra-smart textiles: These materials possess the ability to adapt themselves to an
environmental perturbation or any variation in the signals that they receive. Mainly,
they consist of a central processing unit that acts as a brain having the requisite
predefined programs in place.
Nanoengineered textiles have been designed with a specific modality such as UV
blocking, conductivity, antibacterial properties, hydrophobicity, antistatic behaviour,
energy storage, chromic and sensing properties. This chapter highlights the field of
wearable electronics applications on textiles platform in great focus.
4.1 Smart Textiles for Energy Harvesting and Storage
Energy has been essential to human life and the energy requirement issues in present
times have been a major concern. Smart fabrics have emerged as one of the most
promising platforms to address energy harvesting and storage applications. Based on
this motivation, Wang et al. invented the piezoelectric [107] and triboelectric [108]
nanogenerators in 2006 and 2012 respectively. Our surrounding environment has
abundance in energies including wave, wind, droplet, thermal, chemical and other
mechanical forms. By utilizing the most abundant energies, triboelectric nanogenerators (TENGs) can effectively convert mechanical energy into electrical energy [109],
which facilitates contact electrification and electrostatic induction [109]. Generally,
daily activities of human beings, such as arm movement or footstep of a 65 kg adult
can generate approximately ~67 W of kinetic power [110]. In this context, nanostructured textiles provide a more effective way of approach to scavenge the energy
from human motion. Zhong et al. [111] introduced the first textile based triboelectric nanogenerators. The procedure proposed and developed by Zhong et al. [112]
has been described below: Generally, TENG comprises of four parts that includes
an electrode, positive and negative triboelectric layers, and supporting structures
(substrates, wires, spacers and power management systems, to name a few). The
two dissimilar triboelectric surfaces consist high electron affinity, so that it becomes
the negatively charged triboelectric layer and another layer comprises of positively
charged triboelectric layer. As a result of mechanical friction between the two dissimilar triboelectric layers, electrostatic charges were created and these charges lead
to the development of potential when they are separated by mechanical forces.
The working mechanism behind textile based TENGs is as follows:
1. During the contact establishment between two dissimilar materials under the
tension of mechanical force results in the production of electrical energy due to the