Polyaniline Samples Research Articles

Polyaniline/Graphene oxide composite as an Ultra-Sensitive humidity sensor

This paper investigated the humidity-sensing response of polyaniline/Graphene oxide (PGO) composites. Graphene oxide (GO) was synthesised using the improvised hummers method, and polyaniline (PANI) was synthesised using the chemical in-situ polymerisation process. By adding different weights per cent (wt%) of Graphene oxide (GO) to the polymer matrix, PGO composites were prepared. Structural and morphological properties of GO were confirmed by XRD, RAMAN, FTIR, SEM, EDX, and HR-TEM (elementary mapping) characterisations. The XRD, FTIR SEM and EDX proficiencies were employed to characterise the PGO composites. To experience the humidity response performance, the film of PANI, GO, and PGO samples was groomed by wedging the sample on an IDT substrate using a drop casting technique. Among the samples, the PGO-3 composite (polyaniline/Graphene oxide 15 wt%) depicted a maximum sensing response (SH) of 93.4 % with a dynamic timing behaviour of 4 s and 7 s. The Nobel characters, such as low accurate Sensing response, fewer detection limits (LOD), negligible hysteresis and perfect stability, were observed in the PGO-3 composite. The physical properties such as porosity, water content, and degree of swelling have been outstandingly enhanced in the PGO-3 composite compared to PANI and GO. The mechanism for sensing the PGO-3 composites was deliberately explained based on establishing superficial physisorption, chemisorption layers, and later capillary condensation.

Development of surfactant integrated polyaniline based electrode material towards supercapacitor application

Tailoring electrode material is always important for fabricating high-performance energy storage devices. Polyaniline (PANI) is one of the most-explored electrode materials due to its electroactivity, redox property, easy and cost-effective synthesis and reasonable capacitance. Herein, PANI has been integrated with surfactants (cetyltrimethylammonium bromide, dioctyl sodium sulfosuccinate, sodium lauryl sulphate, Tween-80) via chemical oxidative polymerization pathway and utilized as the electrode material for supercapacitor. Chemical nature, crystallinity and morphology of surfactant integrated PANI samples were evaluated by FTIR, UV–Visible, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques while electrochemical properties were investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy studies. Among the different PANI samples, PANI integrated with cetyltrimethylammonium bromide (PMC) afforded 2.3 times higher capacitance (528 F/g) than PANI synthesized without surfactants (PM) (229 F/g). Due to the influence of CTAB, PMC displayed higher pore volume and lesser particle size as investigated by Brunauer-Emmett-Teller and dynamic light scattering analyses. Furthermore, PMC displayed two times higher electroactive surface area as compared to PM as investigated by cyclic voltammetry studies. It has been observed that the surfactant not only improved the processability of the polymer but also assisted in enhancing the capacitance of the electrode material significantly.

Synthesis and Characterization Conducting Polymer Supported CDS-ZNS Nano Composites Used for Various Applications

Keys include undertaking polymer synthesis and physical property research. Conductive is polyaniline. The presence of pristine nano CdS particles in the matrix was demonstrated by X-ray diffraction (XRD).
 In this study, four sol-gel techniques are used to prepare nanostructured polyaniline (PANI). PANI molecular structure was characterized using X-ray diffraction to assess the morphology of PANI samples.
 The results of the prepared PANI's characterization reveal that the unconventional synthesis methods utilized to create it drastically changed its morphology, chemical composition, crystallinity, conductivity, and surface area. The outcomes of the characterization supported this. The manufacturing and properties of polyaniline conducting polymers are examined in this research. The classic and grafted techniques of polyaniline synthesis have been examined. The relationship between structure and properties is established by this high-accuracy development procedure. In the future, polyaniline with altered structure may be employed.
 PANI/CdS nanocomposites have higher DC conductivity than PANI, according to observations.
 In situ production of conducting polyaniline nanocomposites with CdS nanoparticles was achieved by oxidizing aniline with cadmium sulphate at 3.5 pH. Electrical conductivity of polyaniline is influenced by CdS-nanoparticles. In contrast to pure polyaniline, the electrical conductivity of polyaniline nano-composite is increased by the homogenous intercalation of CdS nanoparticles, which results in a cooperative phenomenon between polyaniline and the nanoparticles.

Synthesis and Characterization of PANI/ZnFe2O4 nRs with Different Doping Concentrations for Potential Applications in Various Fields

The wide-ranging potential of polyaniline (PANI) composites in energy storage, electrochemical, sensing, and electromagnetic shielding applications emphasizes researchers to improve its properties. Here, the doping of ZnFe2O4 nRs by 1, 3, and 5 wt. % within polyaniline has been done. Then, we characterize the doped material using techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR) to verify the successful incorporation of polyaniline onto the nRs. TGA showed that doping of PANI with ZnFe2O4 nRs enhanced the interfacial interactions between the two components. This provided a more stable matrix structure and enhanced the thermal stability of the composite. The transmission of light has been increased by about 18% due to the increase in crystallinity accompanied by ZnFe2O4 doping. As the ZnFe2O4 nRs doping rose, our PANI samples’ optical band gap values slightly decreased by about 10%. In addition, it has been found that the optical characteristics such as refractive index, extension coefficient, surface, and volume energy loss function essentially showed ZnFe2O4 doping dependency. The nonlinear constants of the doped samples have increased due to the new charge carriers and altered the electronic and optical properties of the composite material. Our obtained results show that PANI@ ZnFe2O4 nRs have potential applications such as optical sensors, electrochemical, optoelectronics, and photocatalysis.

Zeolite/polyaniline composite: synthesis and adsorptive properties regarding Cr(VI) from aqueous solutions

The article is devoted to the chemical synthesis of a zeolite/polyaniline (Zt/PAn) composite and a comparative (relative to polyaniline, PAn) study of some of its physicochemical properties, in particular, structural, thermal, and adsorptive (regarding Cr(VI)) characteristics. The results of the studies of spectral, thermal and electrical properties of the initial natural filler mineral (zeolite), synthesized individual samples of polyaniline and Zt/PAn confirmed that the latter are a composite. It was determined that the structure of the polymer in the synthesized samples of both individual polyaniline and the zeolite/polyaniline composite is mostly amorphous and corresponds to the emeraldine salt of sulfuric acid, which is deposited in the form of a thin film on the surface of polycrystalline particles of a finely dispersed mineral. The study of the thermal properties of the samples of individual polyaniline and composite showed that the polymer content in the composite is approximately 50%. The results of studying the adsorption capacity of PAn and Zt/PAn samples proved their high efficiency (98–99%) in removing of Cr(VI) from aqueous solutions. The study of the Cr(VI) adsorption kinetics at its content in the initial solutions of 200–500 mg/L showed that the process is two-stage, and the adsorption capacity of both samples of individual polyaniline and the zeolite/polyaniline composite depends on the concentration of the initial solutions. An increasing of the initial concentration of Cr(VI) in the solutions leads to a certain decreasing in absorption degree and values of adsorption at the first stage of the process by both samples of the PAn and the Zt/PAn. The course of the second stage of sorption, which obviously has the nature of absorption, is longer, but it is during this stage that almost 98–99% removal of Cr(VI) from the investigated solutions is achieved. In particular, it was established that with a Cr(VI) content of 500 mg/L in the investigated solution, the adsorption capacity of zeolite/polyaniline composite samples is 49 mg on 1 g of adsorbent. At the same time, additional studies showed that the adsorption capacity of polyaniline in the sample of the Zt/PAn composite (i. e., without taking into account the mass of finely dispersed mineral filler) reaches 93 mg/g for the identical content of Cr(VI) in the adsorption solution.

Surface Characterization and Electrical Properties of Low Energy Irradiated PANI/PbS Polymeric Nanocomposite Materials

In this work, nanocomposite samples of polyaniline (PANI) and lead sulfide nanoparticles (PbSNPs) were prepared, utilizing the solution preparation method, for implantation in energy storage elements. The PANI/PbS films were irradiated by different fluences of oxygen beam: 5 × 1016, 10 × 1016, and 15 × 1016 ions.cm−2. The composite was investigated by XRD, SEM, DSC, and FTIR. After ion irradiation, the Tg and Tm values decreased by 4.8 °C and 10.1 °C, respectively. The conductivities, electrical impedances, and electrical moduli of untreated and irradiated samples were examined in frequencies ranging from 102 Hz to 5 MHz. Moreover, the ion beam caused a modification in the dielectric characteristics of PANI/PbS. The dielectric constant ε′ was improved from 31 to 611, and the electrical conductivity increased from 1.45 × 10−3 S/cm to 25.9 × 10−3 S/cm by enhancing the fluence to 15 × 1016 ions.cm−2. Additionally, the potential energy barrier, Wm, decreased from 0.43 eV to 0.23 eV. The induced changes in the dielectric properties and structural characteristics of the PANI/PbS samples were determined. These modifications provide an opportunity to use irradiated PANI/PbS samples for several applications, including microelectronics, batteries, and storage of electrical energy.

Effect of Deposition Time on Electrochemical Properties of Polyaniline Samples Prepared by Chemical Bath Deposition

Effect of Deposition Time on Electrochemical Properties of Polyaniline Samples Prepared by Chemical Bath Deposition

Fabrication and Characterization of Free-Standing and Flexible Polyaniline Membranes: Role of Graphene Nanoscrolls

Wearable technologies can contribute to the early and accurate detection of chronic diseases which can be achieved by the integration of biosensors into wearable technologies. However, the challenges associated with the performance of current electrode materials—i.e., flexibility, conductivity, and mechanical stability, made from conducting polymers are preventing their widespread usage. Herein, we report a freestanding and flexible electrode synthesized from polyaniline (PANI) and graphene nanoscrolls (GNS). The PANI-GNS nanohybrid membranes were synthesized via chemical oxidative polymerization and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), nanoindentation (NI), and four-point probe techniques. FTIR results showed an increase in conjugation length of the PANI after the addition of GNS into the mixture which can be indicative of an enhancement of electrical properties. Nanoindentation studies showed an elastic modulus and hardness of 2.6 GPa and 0.17 GPa, respectively, for PANI-GNS-5 nanocomposite, compared to 1.9 GPa and 0.08 GPa, for pure PANI. This was later confirmed by the four-point probe technique as the addition of GNS increased the conductivity of electrodes up to 9 S/cm at a 5% weight ratio. Moreover, SEM results of the PANI-GNS showed an open porous morphology of the polymer matrix in comparison with pure PANI samples which would readily translate into higher amounts of enzyme immobilization on the surface.

Study The Different Concentrations of Hydrochloric and Sulphuric Acid as Dopants for Polyaniline

Conducting polymers have previously been employed in biosensors because they may be used as immobilisation matrices as well as redox systems. Also have numerous uses in medical, pharmacy, environmental monitoring, food and process control. The conductivity of polyaniline-based compositions may be precisely regulated over a broad range. Polyaniline is ease to synthesis, has high conductivity and good performance in biosensor applications. However, polyaniline is not entirely perfect because of its poor solubility in many solvents and low adhesion to different substrate. In this study, hydrochloric acid (HCl) and sulphuric acid (H2SO4) were prepared with different concentration (0.2M, 0.4M, 0.6M, 0.8, 1.0M) for doping process of polyaniline. Fourier-transform Spectroscopy (FTIR), Ultraviolet Spectroscopy (UV-Vis) and Scanning Electron Microscopy(SEM) were used to characterize the properties and morphology of the polyaniline. Four-point probe was used to identify the conductivity of the polyaniline sample. FTIR shows a shift peak at benzenoid rings and quioniod rings. Both acids represent that 1.0 M have high absorbance properties. While SEM shows significant different of agglomeration rate for HCl compared to H2SO4. Lastly, the results showed that the conductivity increasing when the concentration of acids increasing. Doping process helps in enhancing the conductivity properties of polyaniline for biosensor application.

High-Dielectric PVP@PANI/PDMS Composites Fabricated via an Electric Field-Assisted Approach.

Polymer-based composite films with multiple properties, such as low dielectric loss tangent, high dielectric constant, and low cost are promising materials in the area of electronics and electric industries. In this study, flexible dielectric films were fabricated via an electric field-assisted method. Polyaniline (PANI) was modified by polyvinylpyrrolidone (PVP) to form a core–shell structure to serve as functional particles and silicone rubber polydimethylsiloxane (PDMS) served as the matrix. The dielectric constant of the composites prepared under electric fields was improved by the micro-structures formed by external electric fields. With the addition of 2.5 wt% PVP@PANI, the dielectric constant could be significantly enhanced, up to 23; the dielectric loss tangent is only 1, which is lower than that of the aligned PANI samples. This new processing technology provides important insights for aligning fillers in polymer matrix to form composites with enhanced dielectric properties.

Highly conducting PANI- fMWNT composites with exceptional crystallinity and enhanced thermal stability for potential applications

Here we report, the synthesis and characterization of the thin film of polyaniline-functionalized multiwalled carbon nanotube composite with exceptional electrical conductivity, excellent crystallinity and improved thermal stability. In this study, the multiwalled carbon nanotubes were functionalized using formaldehyde through an electrophilic substitution reaction and methylol groups (-CH2OH) attached to the sidewalls of the nanotubes. A significant dispersivity of polyaniline-multiwalled carbon nanotube composites was achieved as a result of the functionalization. The thin film of polyaniline-functionalized multiwalled carbon nanotube composite was prepared via the doping-dedoping-redoping process. The structural, morphological, thermal and conductivity studies of the synthesized polyaniline-functionalized multiwalled carbon nanotube composite samples were carried out using various characterization tools. The thin film sample shows an enhanced electrical conductivity of 1991 S/cm, which is pretty high among the reported values for polyaniline-carbon nanotube composites. It also exhibits an excellent crystallinity of 84.44%, the highest value ever reported. The thermal stability of the thin film sample is very high compared to the polyaniline sample. The charge transfer mechanism in the synthesized samples was investigated using the three-dimensional variable range hopping model. The ANOVA and regression analysis was performed to assess the validity of the model.

Nonlinear optical properties of polyaniline doped with cardanol based dye

We report the third-order nonlinear optical properties of polyaniline doped with an azo dye synthesized using cardanol. Cardanol, which is distilled from CSNL (Cashew Nut Shell Liquid), is a renewable resource since it is a byproduct of the Cashew nut industry. The linear absorption spectrum of the sample was determined in the wavelength range 100 – 800 nm. FTIR spectroscopic data of undoped and azo dye-doped polyaniline samples were compared. The morphology and structure of the azo dye-doped polyaniline are studied using SEM images and XRD. Nonlinear absorption studies were carried out using the single beam z scan technique. A Q-switched Nd: Yag laser operating at 532 nm wavelength with a pulse width of 7 ns was used as the source of light. The nonlinear absorption coefficient and nonlinear susceptibility were determined to be of the order of 10−11 m/W and 10−11 esu respectively. The results indicate that the material is a good candidate for optoelectronic applications.

Positive temperature coefficient of resistance in Na2S interacted polyaniline on cellulose substrate: A flexible electronic material

Flexible electronic materials of polyaniline (PANI) chemically interacted with Na2S have been developed with the objective of improving and tuning its electrical transport properties and optical properties. The chemical interaction of Na2S with PANI was realized by the synthesis process of physical vapor polymerization of aniline over cellulose substrate. The prepared samples of PANI interacted with Na2S at different concentrations (3%, 5%, 7%, and 10%) have been studied through X-ray diffraction (XRD) measurement, scanning electron microscope (SEM) measurement, analysis of FTIR spectra, I-V measurement, and analysis of UV–vis–NIR absorption spectra. From XRD measurement it was observed that the peaks corresponding to the emeraldine form of PANI were obtained during polymerization, which is electrically conductive. Being partially polymerized, this form of PANI provides the scope for further functionalization through chemical interaction with Na2S. As a consequence of chemical interaction with Na2S, its resistivity was found to increase systematically with the increase of concentration of Na2S. A twelve times change in resistivity was recorded with Na2S interaction. The temperature dependence of electrical conductivity shows an excellent positive temperature coefficient of resistance, which is of profound technological significance for self-controlled overheating protection of electronic devices.

Study of Different Acid Doped Polyaniline Nanostructures and Their Electrical Conductance Properties

The different acid doped polyaniline (PANI) materials were prepared in situ using mineral acids like HCl, H2SO4, HNO3 and HClO4 of different concentrations in presence of 0.2 M aniline solution and 0.25 M ammonium persulfate as oxidising agent by the chemical oxidation method. The synthesized materials were studied for their physico-chemical characterizations like XRD, IR and SEM. IR studies revealed the formation of emeraldine salt in all the acid doped PANI samples. XRD of samples exhibited the partly crystalline structure of which HClO4 doped showed good crystallinity over other samples. SEM images displayed the formation of nanorods like structural agglomerates. The effect of acid dopants on their electrical conductivity was investigated by using the four probe set up technique. It was found that HClO4 doped PANI exhibited good electrical conductivity over the other acid doped samples whereas the lowest electrical conductivity was recorded for HNO3 doped PANI samples. The electrical conductivity of 1 M HClO4 doped PANI was the highest i.e. 9.1 S cm-1 among all PANI samples.

Effect of Oxidizer on PANI for Producing BaTiO3@PANI Perovskite Composites and Their Electrical and Electrochemical Properties

Polyaniline (PANI) has received significant attention in basic and applied studies because it has electrical and electrochemical properties comparable to conventional semiconductors and metals. PANI's electrical and electrochemical properties can be controlled through its preparation methods. Accordingly, in the present work, two different samples of PANI were prepared by the polymerization of aniline monomer via in situ polymerization method using two different oxidizers of dichromate (PANI (1)) and persulphate (PANI (2)). The products were blended with BaTiO3 (BTO) to form BTO@PANI composites. The composites were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). SEM illustrated the covering of PANI layers on the BTO nanoparticles. The electrical and electrochemical properties of the prepared composites were studied. The BTO@PANI(2) composite sample showed a conductivity of 1.2 × 10–3 S/cm higher than that found for each BTO@PANI(1) 9.1 × 10–4 S/cm and its constituents. The supercapacity showed higher capacity values of 70 F/g, and 76 F/g for BTO@PANI(1), and BTO@PANI(2), respectively, which are higher than its constituents.

Fabrication and characterization of heterojunction made of porous silicon and polyaniline synthesized by chemical and electrochemical routes

Polyaniline (PANI) samples were deposited through chemical and electrochemical routes onto macroporous silicon (MPS). Their chemical and electrical features were investigated. For this, Fourier transforms infrared, Raman, and energy dispersive spectroscopies were used to show the successful incorporation of PANI into the pores and the formation of silicon oxide as a consequence of the silicon instability in the aqueous solution. The electrical parameters extracted by fitting the current-potential curves using the thermionic emission model of two opposite diodes being one at the PANI/MPS interface and the other at the silicon/back contact, indicate a Schottky barrier of about 0.730 V at the first interface and between 0.795–0.840 V at the second one and becomes more significant in the measurements between two contacts at the PANI surface. The chemical analysis reveals the presence of silicon oxide in both structures. This compound was found to be the determining factor for changing the electrical behavior. A larger flat band was measured in the device made by the chemical synthesis of PANI. The impedance analysis has shown that charge transfer is determined not only by the PANI and silicon oxide conductivity but also by the depletion layer's electrical features. However, the differential activation energy analysis indicates that PANI is chemically deposited, and the charge transport occurs hopping conduction. In contrast, in the electrochemically one, the charge is through impurity band conduction.

Structure and thermoelectric behavior of polyaniline-based/ CNT-composite

Thermoelectric materials have the capability of harvesting and converting the heat wasted into useful electrical current. Polymer thermoelectric composites have recently received attention and experienced a rapid development because of their low density, versatility, ease of synthesis and processing and low thermal conductivity. Herein, we report on synthesis and characterization of pristine polyaniline and polyaniline/carbon nanotubes network nanocomposite. In the preparation, aniline was polymerized via a facile chemical oxidative polymerization process, in which 30 wt% multiwall carbon nanotubes were in situ incorporated. Both pristine polyaniline and its composite were examined by XRD. For their thermoelectric performance, Seebeck coefficient and electrical conductivity were characterized using a home-built setup operated by keithley Multimeter (Model:2000). The fabricated composite exhibited superior increase in Seebeck coefficient and power factor to reach 141 μV/K and 0.004 μW/mK2, respectively at 95 °C. The corresponding I–V curves were further measured. The current was found to increase substantially to reach 2.2 mA at 1 V; almost one order of magnitude higher when compared to that of the pristine polyaniline sample.

Comparative analysis of absorption capacity of Cr(VI) polyaniline and cellulose/polyaniline composites synthesized in aqueous solutions of organic acids

Samples of polyaniline (PAn) doped by different organic acids, namely PAn-FA, PAn-AA, PAn-OA, and PAn-CA, were synthesized by oxidation of aniline (An) with ammonium peroxydisulfate in the 0.5 M aqueous solutions of formic (FA), acetic (AC), oxalic (OA), and citric acids (CA) respectively. Samples of composites of cellulose (Cel) with doped polyaniline (Cel/PAn-FA, Cel/PAn-AA, Cel/PAn-OA, and Cel/PAn-CA)were produced by the same method under the presence of a suspension of microfibrillar bleached cellulose in the reaction mixture. The mass ratio of An : Cel was 1 : 1. The structure of obtained samples was studied using X-ray diffraction, FTIR spectral analysis, and scanning electron microscopy. Adsorption capacity as concerns Cr(VI) by produced samples of both individual polyanilines and composites and adsorption kinetics has been studied by electronic (UV) and fluorescence X-ray spectroscopy and also X-ray energy dispersion analysis methods. Practically full removal of Cr(VI) ions (98–100 %) of such investigated samples of PAns and its composites has been determined. The adsorption kinetics is well described by equations of pseudo first and second orders. According to the results, the Langmuir and Freundlich adsorption isotherms are plotted. It was found that the process of adsorption Cr(VI) ions by doped samples of PAn and Cel/PAn accords to adsorption model of Langmuir. It has been shown, that adsorbed chromium remains in the samples of adsorbents in the form of chromium (III). Keywords : polyaniline, cellulose, composites, structure, Cr(VI), adsorption.

Cr(VI) removal from the aqueous solutions by the samples of polyanyline doped with phosphoric acid

Samples of polyaniline (PAn) were synthesized by oxidative polycondensation of aniline in the presence ammonium peroxydisulfate in the aqueous solutions of phosphoric acid (PA) of different concentrations (0.16–3.30 M). Produced polyaniline was in the form of the emeraldine salt of phosphoric acid (PAn–PA). The prepared samples were used to study in the static conditions of their adsorption properties with regard to Cr(VI) from the aqueous solutions of different concentrations, namely 50, 100, 150, 200 and 300 mg/L, accordingly to the following technique: the 10 ml of the K 2 Cr 2 O 7 solution with appropriate concentration has been added to the portion of adsorbent sample, recorded time and at certain intervals took samples with a volume of 500 μl. These selected samples have been placed into the quartz cuvette with 2 mm thick and has been photometered. The amount of adsorpted substance was determined by the calibration plot. The adsorption experiments were carried out under the temperature 20±1°С. It is shown that the percentage of Cr(VI) removal by PAn samples reaches 94–99 %. It was found that the sorption capacity of all PAn–PA samples increases with increasing phosphoric acid concentration in the reaction mixture during synthesis. Analysis of the IR-FT spectra of PAn–PA samples shown that the partial oxidation of the emeraldine salt to pernigraniline takes place in the result of Cr(VI) adsorption. It was demonstrated that this process can be described sufficiently good by Langmuir or Freundlich adsorption isotherms, while the kinetics of process is in good agreement with model of pseudo second order. As a result of research, the possibility of the using of PAn samples, where polymer is doped with phosphoric acid during synthesis, for sorption of Cr(VI) from aqueous solutions without their additional acidification, has been determined. Keywords : polyaniline, Cr(VI) sorption, kinetics.

Cr(VI) adsorption by the polyanyline and zeolite/polyaniline–sulphuric acid composite

The adsorption properties of the samples of polyaniline (PAn) and zeolite/polyaniline (Zt/PAn) composite regard to Cr(VI) have been studied. The samples of the PAn and Zt/PAn composite were prepared in the 0.5 M sulfuric acid aqueous solution by oxidative polycondensation of aniline by ammonium peroxydisulfate respectively under the presence and absence of the zeolite powder in the reaction mixture. The molar ratio of aniline to ammonium peroxydisulfate during synthesis was 1 : 1.1, while the weight ratio of aniline to zeolite was equal to 1 : 1. The formation of PAn and Zt/PAn composite was confirmed by X-ray phase analysis, FT-IR spectroscopy, thermogravimetric studies and results of electrical conductivity measurements. Analysis of the spectral, thermal and electrical properties of the synthesized samples of Zt/PAn composites showed their essential differences in relation to individual samples of the zeolite and polyaniline. It was determined that the structure of polyaniline in the synthesized samples of PAn and Zt/PAn is amorphous with insignificant inclusions of polyaniline crystallites (in the form of emeraldine salt of sulfuric acid) deposited on polycrystalline zeolite particles as carrier-matrices. Thermogravimetric studies of PAn samples and Zt/PAn composites confirmed the composition of composites and the dependence of their thermal stability on the content of natural mineral. The defined values of the specific conductivity for the synthesized samples of zeolite/polyaniline composites confirmed the presence of sulfuric acid in the composites. It is determined the availability and high efficiency of the use of PAn and Zt/PAn composites, in which polyaniline is doped by sulfuric acid during synthesis, for Cr(VI) sorption from aqueous solutions. It was demonstrated that Cr(VI) adsorption by produced samples can be described sufficiently good by Langmuir or Freundlich adsorption isotherms, while the kinetics of process is in good agreement with the model of pseudo second order. Keywords : polyaniline, zeolite/polyaniline, properties, adsorption of Cr(VI).