Structural and electrical properties of polyaniline/silver nanocomposites

Abstract

Polyaniline (PANI)/Ag nanocomposites were prepared by separate synthesis of silver nanoparticles by inert gas condensation, incorporating in the 1-methyl-2-pyrrolidinone (NMP) solution of polyaniline emeraldine base (PANIEB) and then cast into films at 120 °C. X-ray diffraction confirmed the presence of ∼67 nm silver nanoparticles in the polyaniline matrix. From the thermogravimetric analysis it is observed that the nanocomposite films have a higher degradation temperature than the pure PANI film. Scanning electron microscopy showed a uniform distribution, with spherical and granular morphology for low concentration of Ag nanoparticles, whereas for higher concentration (1.0% Ag) nanorods are formed. The impedance spectroscopic studies of NMP plasticized nanocomposite films suggest microphase separation into reduced and oxidized repeat units. Incorporation of silver nanoparticles in PANI reduces the charge trapping centres and increases the conducting channels, which causes a tenfold decrease in the real part of impedance.

Temperature characterization of dielectric permittivity and AC conductivity of nano copper oxide-doped polyaniline composite

“…is the angular frequency of applied electric field and n 1 is a factorial exponent. 29,30 The doping of conjugated polymers generates high conductivities by increasing the carrier concentration n. The polymer is oxidized by the acceptors (removal of electron), thereby producing a radical cation (hole) on the chain that does not delocalize completely, but is delocalized only over a few monomeric units deforming the polymeric structure. This radical cation with lattice distortion around the charge is called a polaron.…”

“…The increasing ac at higher frequencies is attributed to charge motion in the amorphous regions and this supports the presence of isolated polarons and bipolarons in this region. 30 This indicates that there may be charge carriers which can be transported by hopping through the defect sites along the polymer chain. The frequency-dependent AC conductivity of PANI/CuO increases as the temperature increases for a particular frequency.…”

Molecular structure, optical, electrical and sensing properties of PANI-based coatings with silver nanoparticles deposited from the active gas phase

“…Several researchers have successfully applied frequency mapping of the imaginary part of the electric modulus M to describe the occurring relaxation processes for PANI coatings at high frequency range [12,13]. The M curves for the PANI − AgCl and PANI + AgCl coatings are shown in Fig.…”

“…studied and selectivity of the composite electrophysical sensors to ammonia. This effect has and it is associated with both the increase in the conductivity of PANI/Ag composite system [12] and the formation of Ag x O semiconducting oxide shell of silver nanoparticles, the conductivity of which depends on the sorption of ammonia [8].…”

Growth of polyaniline nanofibers for supercapacitor applications using successive ionic layer adsorption and reaction (SILAR) method

“…Among the conducting polymers, polyaniline has been studied for its desirable properties, such as controllable electrical conductivity and optical, chemical and electrochemical properties, its easier and inexpensive preparation methods, and its low cost compared with inorganic semiconductors [5]. Potential applications of polyaniline include electromagnetic shielding, organic lightweight batteries, microelectronics, sensors, ionic exchange, corrosion protection, and semiconductor devices, electrochromic devices, supercapacitors and gas separation membranes [6][7][8].…”