In all conducting polymers (CPs), polyaniline (PANI) is one of the most thoroughly studied CPs. An essential feature of PANI is that its repeating units have two different moieties in different weights: oxidized and reduced state. In light of this element, PANI might be doped to get new molecular structures with various properties. It is considered as a (p-type) material, since it has excellent mechanical flexibility and environmental stability, and its conductivity could be controlled with acid/base (doping/undoping), it has potential applications in numerous fields, for example, lightweight battery electrodes, electromagnetic shielding devices, anti-corrosion coatings, and sensors. This chapter is focused on PANI as a leading polymer and brief synthesis of PANI thin films by the diverse strategies pursued by various applications in different fields.
TopIntroduction
Conducting polymers (CPs) are specifically compelling for materials inquire about as their electric properties make them a promising option in contrast to inorganic semiconductor materials. Additionally, they are substantially more effortlessly fabricated and can be demonstrated into specific molecular structures with explicit properties, which makes them appropriate for an expansive scope of uses.
The electric conductivity of polymers can be adjusted, really upgraded, by doping, a procedure comprising in the compound or electrochemical joining of positive charges (p-doping) or negative charges (n-doping) into the molecular grid. Contingent upon the sort of doping, regardless of whether n or p, the polymer particle is transformed from an unbiased state into a diminished or oxidized state, separately. The oxidation and decrease forms thus rely upon the synthetic substances that are utilized as dopants (Baibarac et al., 1999).
Among various conductive polymers, polyaniline has gotten a lot of consideration because of its environmental stability, high conductivity, simple blend, simply dealing with, and ease monomer. Research on the union and portrayal of PANI has pulled in incredible consideration for most recent two decades because of their extensive variety of promising applications (Tan et al., 2011; Zeng et al., 2010). PANI may present in different oxidation states, which are characterized by the proportion of amine to imine nitrogen particles in its spine. Leucoemeraldine (PANI-LE) base form of PANI is totally reduced form, whereas pernigraniline (PANI-PE) base is completely oxidized form. Similarly, the emeraldine base (PANI-EB) is half oxidized, and half reduced form of PANI. Upon protonic corrosive or electrochemical de-doping/doping, the polyaniline materials can be deprotonated/protonated, experiencing an inward redox response, changing their properties, for example, colour (Fu et al., 2014; Chauhan et al., 2013; Jangid et al., 2014), making it a polyelectrochromic material, and conductivity. The protonated type of the most well-known polyaniline express, the blue PANI-EB, is the green directing emeraldine salt (PANI-ES) (Jangid et al., 2014; Jangid et al., 2015a; Jangid et al., 2015b; Ping et al., 1997).
These ones of a kind properties have made polyaniline reasonable for use in various electrical applications, for example, rechargeable batteries (Mu et al., 1998; Sivakkumar et al., 2007), supercapacitors (Liu et al., 2011; Wang et al., 2009), fuel cells (Gajendran et al., 2008) delicate electrochemical sensors and biosensors (Rajesh et al., 2009; Jangid et al., 2014). An essential normal for PANI lies in the way that its rehashing units contain two distinct substances in various weights: a reduced state and an oxidized state. In view of this element, PANI might be doped to acquire new molecular structures with various properties. The examination of their vibrational properties, which rely upon their composition and doping state, is especially noteworthy. In both central and expansive scope of uses conducting polymers are utilized as thin films, for which explicit exploratory need to received and created.