Polyaniline Nanostructures Research Articles

Flexible Hybrid Supercapacitor Achieving 2.2V with NiCo2S4/Polyaniline/MnO2 and N, S-Co-Doped Carbon Nanofibers for Ultra-High Energy Density.

Flexible all-solid-state asymmetric supercapacitors (FAASC) represent a highly promising power sources for wearable electronics. However, their energy density is relatively less as compared to the conventional batteries. Herein, a novel ultra-high energy density FAASC is developed using nickel-cobalt sulfide (NiCo2S4)/polyaniline (PANI)/manganese dioxide (MnO2) ternary composite on carbon fiber felt (CF) as positive and N, S-co-doped carbon nanofibers (CNF)/CF as negative electrode, respectively. Initially, porous δ-MnO2 nanoworm-like network is decorated on CF using potentiodynamic method. Subsequently, interconnected PANI nanostructures is grown on the MnO2 via a facile in situ chemical polymerization, followed by the electrodeposition of highly porous NiCo2S4 nanowalls. Benefiting from 3D porous structure of conductive CF and redox active properties of NiCo2S4, PANI and MnO2, FAASC achieved a superior energy storage capacity. Later, high-performance N, S-co-doped CNF/CF negative electrode is synthesized using electropolymerization of PANI nanofibers on CF, followed by the carbonization process. The assembled FAASC exhibits a wide voltage window of 2.2V and remarkable specific capacitance of 143 F g-1 at a current density of 1 A g-1. The cell further delivers a superb energy density of 71.6Wh kg-1 at a power density of 492.7W kg-1, supreme cycle life and remarkable electrochemical stability under mechanical bending.

Microwave-plasma surface modification of nanostructured-polyaniline:graphite composite counter electrode in dye-sensitized solar cells

This work demonstrates microwave plasma surface modifications of nanostructured polyaniline (NPES)-based counter electrodes (CE). Oxidative oxygen (O2) plasma and reductive hydrogen (H2) plasma were used in this study. Optical emission spectra confirm the presence of reactive species in both plasmas through the emissive species, such as O2+, O+, O•, H(nl), and H2 Fulcher-α. Microwave plasma treatment does not affect the surface morphology of NPES composite CE, which conserves its granule nanostructures, as revealed by SEM. The water contact angle measurements demonstrate how the O2 plasma treatment improves surface hydrophilicity, contrary to the H2 plasma treatment. Raman spectroscopy results show significant changes in the intrinsic-oxidation state and the number of semiquinonoid species (SQ) of NPES after plasma treatments, which are represented by the ratios of Raman intensity at 1368–1260 cm−1 and 1624–1583 cm−1, respectively. Generally, O2 plasma treatment increases the intrinsic-oxidation state and SQ number, opposite to the H2 plasma. The optimum condition of microwave plasma-assisted surface modification was attained in one minute of O2 plasma treatment, producing NPES with the highest intrinsic-oxidation state and SQ number. A power conversion efficiency of 3.17 % was obtained by a dye-sensitized solar cell fabricated with a modified CE using a one-minute O2 plasma treatment.

Preparation and investigation of Montmorillonite-K10 Polyaniline nanocomposites for optoelectronic applications

One-dimensional polyaniline (PANI) nanostructures were synthesized in situ in the presence of two-dimensional (2D) Montmorillonite (MMT) clay nanosheets. Strong interactions between the polymer and MMT platelets in the nanocomposites were confirmed through spectroscopic studies. X-ray diffraction and scanning electron microscopic studies revealed the clay's profound effect on the polymer's crystallinity and morphology. The clay nanosheets induced higher crystallinity and well-defined nanorod morphology in the polymer structure. Consequently, the nanocomposite showed an electrical conductivity of 8.72 S/cm, closer to that of the pristine polymer (8.97 S/cm), despite the presence of highly insulting clay material. Surprisingly, a notable decrease in the optical bandgap of the polymer from 3.73 to 2.88 eV of the nanocomposite was also observed. This novel integration of a narrow band gap and high conductivity in PANI/MMT nanocomposites can expand their utility for visible light interactions in areas encompassing photocatalysis, photovoltaics, electro/photochromism, and related technologies.

Energy-Efficient Nanostructured Ion Exchange Membranes from Functionalized Poly (2,6-Dimethyl-1,4-Phenylene Oxide)

Highly energy efficient and ion permeable ion exchange membranes are in high demand in many modern sectors to clean water, transform energy, and store energy in devices like electro-dialyzer, fuel cells, and batteries. However, greater resistance and reduction in ion permeation of conventional membranes dictate the desire for nanostructured functional ion exchange membranes. This project proposes the fabrication of ion exchange membranes using electroactive nanostructured polyaniline incorporation into ion exchange materials, electrostatically interaction between polymer and nanostructured electroactive material overcomes the problem of high resistance and less ion permeation. Solution casting and post-drying techniques are used for membrane casting. Nanostructured electroactive material helps to increase ionic conduction thus reducing 17% resistance for functional cation exchange membrane (FCEM) and 12% for functional anion exchange membrane (FAEM) also assisting to increase ion permeation. Hydrophilic nanostructured polyaniline electroactive material holds more water and increases water uptake. Cross-linking increases stability as well as reduces 17% and 8% swelling degrees for FCEM and FAEM respectively. Besides the electrochemical property offers an increase limiting current density of 38%, 23% for FCEM and FAEM respectively, and 19% higher desalination performance than non-nanostructured sulfonated polyphenylene oxide (CEM) and quaternized polyphenylene oxide (AEM) membranes.

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.

Emulsion-assisted polyaniline grown on molybdenum diselenide nanoflowers for efficient counter electrode application in dye-sensitized solar cells

ABSTRACT Molybdenum diselenide (MoSe2) is often composed with conducting polymers like polyaniline (PANI) to lower the stacking and increase the active sites for catalysis. The method of polymerization and the concentration of monomer play a significant role in the growth of PANI nanostructures over the MoSe2 surface. Here, MoSe2-PANI nanocomposites have been synthesized with different molar concentrations of the monomer in the emulsion of chloroform and distilled water using ammonium persulfate (APS) as the initiator. The increased surface area of the composite MPAN (1:1) compared to pristine MoSe2, as observed from the FESEM and BET study, is fruitful for counter-electrode application in dye-sensitized solar cells (DSSC). The lower Rct values for the MPAN (1:1) and increased current in cyclic voltammetry further approved the suitability of the MoSe2-PANI as a counter electrocatalyst. The counter electrodes against N719 dye-sensitized TiO2 photoanode in DSSC yielded the best results for MPAN (1:1), generating an efficiency of 6.45%.

Polyaniline Nanostructures Embedded Ethylcellulose Conductive Polymer Composite Films-Based Triboelectric Nanogenerators for Mechanical Energy Harvesting and Self-Powered Electronics

Polyaniline Nanostructures Embedded Ethylcellulose Conductive Polymer Composite Films-Based Triboelectric Nanogenerators for Mechanical Energy Harvesting and Self-Powered Electronics

Electrochemical sensor based on polyaniline supported CdS/CeO2/Ag3PO4 nanocomposite for Malathion detection

Different nanomaterials in single (CeO2), binary (CdS/CeO2 and Ag3PO4/CeO2), ternary CdS/CeO2/Ag3PO4 (4:1 molar ratio) and conductive polymer supported (PANI-CdS/CeO2/Ag3PO4) were synthesized by co-precipitation method. Elemental analysis, crystal structure, surface area, morphology and optical properties of the as-synthesized nanoparticles were characterized. Electrochemical behavior of glassy carbon electrode modified by polyaniline supported CdS/CeO2/Ag3PO4 nanocomposite were also characterized by electrochemical impedance spectroscopy and cyclic voltammetry in 0.1 M of K3[Fe(CN)6] containing 0.1 M KCl at pH 7 with a frequency range of 0.1 to 1000 Hz, with an amplitude of 50 mV. The voltammogramm shows that the process of all as synthesized nanocomposites modified glassy carbon electrode is diffusion controlled. Under optimum conditions, the electrochemical sensor showed Malathion concentrations in linear range of 1-13 × 10−7 M, good reproducibility, and no interference by other pesticides and high recovery values around 98.90%. As-synthesized nanocomposite modified glassy carbon electrode exhibits the lowest detection limit of 3.0 × 10−9 M for Malathion detection. The simplicity of preparation, high sensitivity, good stability and reproducibility of this nanostructured polyaniline supported CdS/CeO2/Ag3PO4 electrode can be a potential candidate for application in the detection of Malathion.

Highly sensitive Non-enzymatic, Non-Invasive Disposable Electrochemical Polyaniline Nanocaps based Sweat Sensor for Glucose Monitoring

Diabetes has surged dramatically, leading to a significant healthcare burden worldwide. Consequently, there is a growing need for reliable non-invasive alternatives for glucose monitoring, replacing traditional blood-based analysis. Despite this, enzyme degradation and stability have posed challenges for sweat sensors. To address these obstacles, the present study emphasizes the development of a novel, non-enzymatic electrochemical sweat sensor for glucose monitoring that is painless, reliable, and based on polyaniline nanocaps. Polyaniline (PANI) nanostructures, including nanocaps, nanowires, and nanocollides, were successfully synthesized using sodium dodecyl sulphate (SDS) as a template at varying ratios. The obtained nanostructures were characterized using XRD, FTIR, FESEM, and TEM. For electrochemical analysis, a screen-printed carbon electrode (SPCE) was employed. The presence of subsistent polyaniline nanocaps structure resulted in better catalytic performance, exhibiting superior sensitivity of 94.3859 µA mM−1 cm−2 and a limit of detection (LOD) of 0.04 µM in the linear range of 10–500 µM for glucose monitoring. Furthermore, the stability of the modified PANI nanocaps@SPCE sensor was tested using a mimic sweat sample. These results suggest that the fabricated PANI nanocaps@SPCE sensor holds promise as a non-invasive sweat sensor for glucose monitoring.

Plasmonic grating H2S sensor based on a chitosan-polyaniline-nano-composite

In this study, a plasmonic sensor was designed based on the grating coupling to detect the low concentration of H2S as a toxic chemical. The polyaniline nanostructure was prepared using the laser ablation technique in a chitosan solution and the final products were tested using analytical methods. The chitosan-polyaniline nanocomposite layer was used as a sensing layer and coated on the surface of 1D polydimethylsiloxane grating. The variation of reflectivity with different concentrations of H2S was registered from the surface of the grating for evaluating the sensor’s response. Finally, it was explained using the Langmuir isotherm absorption model. The limit of detection and the sensitivity of chitosan-polyaniline-nanocomposite were about 1 ppm and 0.10767 for the detection of H2S, respectively.

Polyphenylsulfone membrane blended with polyaniline for nanofiltration promising for removing heavy metals (Cd2+/Pb2+) from wastewater

This study reported polyaniline (PANi), an emerging multifunctional nanomaterial, for fabricating the polyphenylsulfone (PPSF)–PANi nanocomposite membrane for nanofiltration (NF) to remove heavy metals (Cd2+/Pb2+) from wastewater. PANi was synthesized via oxidative polymerization of an aniline monomer at a low concentration (≤0.1 M). Furthermore, the nanostructure of PANi was determined using transmission electron microscopy. The membrane structure and characteristic properties were studied in terms of surface and cross-section morphologies, topography, hydrophilicity, and surface charge using scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle (CA) measurement, and zeta potential measurement, respectively. Thermal and mechanical properties and casting solution viscosity were also studied. The SEM results demonstrated that PANi inclusion helped to construct a typical asymmetric membrane with a pore size of ∼1 nm. Additionally, it enhanced the surface properties, which was indicated by a more considerable hydrophilicity (CA ≤ 52) and a shift in the zeta potential from −40 to −10 mV. Increasing the PANi concentration from 0.25 to 0.50 wt% aided the heavy metal rejection by the nanocomposite membrane, affording an increase of the Cd2+/Pb2+ rejection. However, the Cd2+/Pb2+ rejection decreased when the PANi concentration was 1.0 wt%. The optimized PPSF–PANi nanocomposite membrane at 0.50-wt% PANi exhibited a water permeability of 1.8 LMH/bar and high rejections of 99% and 95% toward Pb2+ and Cd2+, respectively. Tensile strength and TGA tests also revealed the role of PANi as a positive reinforcement on the mechanical and thermal properties of the membrane.

Preparation of Anionic Surfactant-Based One-Dimensional Nanostructured Polyaniline Fibers for Hydrogen Storage Applications

Polyaniline fibers were prepared in the presence of anionic surfactant in an ice medium to nucleate in one dimension and were compared to bulk polyaniline prepared at an optimum temperature. Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) were used to investigate the structural analysis of the prepared samples. A conductivity study reveals that polyaniline fibers have high conductivity compared to bulk polyaniline. Hydrogen storage measurements confirm that the polyaniline fibers adsorbed approximately 86% of the total actual capacity of 8-8.5 wt% in less than 9 min, and desorption occurs at a lower temperature, releasing approximately 1.5 wt% of the hydrogen gases when the pressure is reduced further to 1 bar.

Compositing Nanostructured Polyaniline with Single-Walled Carbon Nanotubes for High Thermoelectric Performance

In the face of the growing energy crisis and demand on environmental protection, organic thermoelectric (TE) materials have been coming under the spotlight from global researchers as a potential countermeasure. However, there have been few studies on the relationship between the morphology of conductive polymers (CPs) and their TE performance. In this work, nanostructured polyaniline (PANI) was synthesized by interfacial polymerization with the addition of organic solvents of different polarities, including cyclohexane (CYH), carbon tetrachloride (CCl4), toluene (MB), dichloromethane (DCM), and dimethyl sulfoxide (DMSO). Physical mixing PANI with single-walled carbon nanotubes (SWCNTs) affords PANI/SWCNT composites. The composite of PANI nanobelts and 10 wt% SWCNTs achieves a power factor (PF) of 5.13 ± 0.56 μW m-1 K-2 at room temperature (RT). Spherical PANI doped with 50 wt% SWCNTs followed by pressing affords maximal room temperature PF value of 178.10 ± 3.77 μW m-1 K-2. A prototype TE generator (TEG) constructed with seven pairs of legs of as-prepared PANI/SWCNT composites and their n-type counterparts generates voltage of 10.27 ± 0.15 mV and output power of 36.65 ± 1.18 nW at temperature difference of about 50°C. This work illustrates that well-regulated PANI nanostructure could significantly affect the TE properties of PANI/SWCNT composites, which are promising in future preparation of high-performance polymer-based composites regarding the fabrication of TE devices suitable for harnessing low-grade waste heat.

Anthraquinone-2-sulfonic acid-loaded polyaniline nanostructures: Construction of symmetric supercapacitor electrodes thereof

Polyaniline (PANI) nanostructures were synthesized via an acid-free green route using redox-active, water-soluble 9,10-Anthraquinone-2-sulfonic acid sodium salt (AQSA). As a counter anion for the PANI backbone, the AQSA plays an important role in polyaniline (PANI) chain growth and as a morphology regulator. The AQSA doped PANI shows pronounced specific capacitance with effective cycling stability. As-synthesized nanotubular structures of PANI_AQSA (0.5, 1.0, and 1.5) with various concentration ratios of aniline to AQSA were achieved in appreciable yield. The intrinsic physico-chemical properties were analyzed using various physico-analytical techniques such as Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), powder X-ray diffraction analysis (XRD), Fourier Transmission Infrared spectroscopy (FT-IR), X-ray Photo Electron Spectroscopy (XPS), and Raman analysis. Nanotubular structures of PANI_AQSA were analyzed using FESEM studies. The electrochemical studies, galvanostatic charge-discharge (GCD), and Electrochemical impedance spectroscopy (EIS) were methodically investigated. PANI_AQSA_1.5 portrays enhanced specific capacitance of 440 Fg−1 at 1 Ag−1 (three-electrode system) in 1 M sulphuric acid electrolyte than its regular Cl− counter ion (276 Fg−1 at 1 Ag−1). The fabricated symmetric PANI_AQSA//PVA_H2SO4//PANI_AQSA supercapacitor showed a specific capacitance of 391 Fg−1 at 1 Ag−1 with 93 % capacitance retention for ~1000 cycles.

Synthesis and formation mechanism of PANI nanotubes prepared via facile aqueous solution polymerization

Polyaniline nanotubes were fabricated using itaconic acid as dopant and soft template via facile aqueous solution polymerization. On basis of scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), the influence of polymerization conditions such as oxidizer/aniline molar ratio and oxidizer concentration on the morphology and chemical structure of PANI was studied. Polyaniline nanotubes with 3D porous network structure were successfully prepared under the optimal conditions. The formation mechanism of PANI nanotubes was thoroughly analyzed by the measurements such as transmission electron microscopy (TEM), 1H nuclear magnetic resonance (NMR), the diffusion ordered spectroscopy (DOSY) and relaxation time (T1 H) measurements. Itaconic acid micelles were used as "soft template" to form self-assembled polyaniline nanostructures. Meanwhile, in the micelles composed of aniline and itaconic acid, the aniline cations initiated by oxidizer free radicals were polymerized into polyaniline with the structure of nanotubes. Furthermore, the formation of polyaniline nanotubes was guaranteed by the double electric layer structure.

Continuous long-term glucose biosensor in agitation condition for bioconversion processes

The use of a glucose biosensor in the bioconversion processes is challenging due to a long period of intensive stirring that is required to mix the heterogenous substants together. In this work, a glucose biosensor was developed to be accurate and robust for an extended period of measuring time in agitated conditions. The sensor probe was fabricated by electro-polymerization of polyaniline (PANI) nanostructures on a gold wire before putting in gold nanoparticles (AuNPs) and carrageenan (carr) solution to make an PANI-carr-AuNPs layer. Then the probe was soaked in PQQ-Glucose dehydrogenase (GDH) solution before coating with polyurethane (PU) to prevent the enzymes from leaching away from the sensor. The sensor probe showed a sensitivity of 0.85 μA/mg/ml of glucose with R2 of 0.9973. The storage stability of the probe was up to 4 days with stable signal. In agitated condition of 150 rpm, steady signals from the sensor were continuously obtained for 72 h. In sugarcane bagasse hydrolysis with speed at 150 rpm for 72 h, the biosensor continuously displayed signals which were not significantly different in glucose concentration to the results from the HPLC method. This biosensor displayed promising applications in bioconversion processes.

Morphology control of polyaniline nanostructures on the surface of reduced graphene oxide/cotton fabric composite electrode for high-performance wearable supercapacitor application

Morphology control of polyaniline nanostructures on the surface of reduced graphene oxide/cotton fabric composite electrode for high-performance wearable supercapacitor application

Development of CNTs-carbonized cotton fiber/PANI 3D-nanocomposites for flexible energy storage and electromagnetic shielding applications

In this study, three-dimensional (3-D) architectures consisting of nanostructured polyaniline (PANI) and carbon nanotubes (CNTs) grown on carbonized cotton cloth (CC) were prepared and used as supercapacitors and electromagnetic interference (EMI) shielding materials. The surface morphology and mass of PANI on CNTs were altered by changing the concentration of aniline (AN) precursor in the polymerization reaction. It is found that when the PANI content on CNTs increased, the electric conductivity of nanocomposites decreased and the charge transfer resistance increased remarkably. The highest PANI-deposited nanocomposite was used to fabricate a proof-of-concept symmetric two-electrode supercapacitor, which exhibited an excellent areal specific capacitance of 3.1 F cm–2 (equivalent to a specific volumetric capacitance of 100.5 F cm–3) at the current density of 2.0 mA cm–2. In addition, the EMI shielding performance of the developed nanocomposites was studied, and the results revealed that 3 layers of nanocomposites with a thickness of less than 1 mm demonstrated an excellent shielding capability with total shielding effectiveness above 40 dB. Based on those findings, it is anticipated that the presented nanocomposite would be a potential candidate for flexible energy storage and EMI shielding applications.

Polyaniline-Based Rose-like Chiral Nanostructures for Raman Enhancement

Metal-free materials for efficiently enhancing Raman spectrum represent a Frontier in the field of Raman enhancement. Herein, a metal-free Raman enhancement-active material, polyaniline (PANI)-based rose-like chiral nanostructures, which is fabricated by the oxidation polymerization of aniline occurred in a reaction droplet on a glass slide, is developed. The morphology of the as-prepared PANI nanostructures is well designed to rose-like chiral (left-handed or right-handed) nanostructures. Due to the suitable energy level and chiral nanostructure feature, the prepared PANI nanostructures exhibit excellent Raman enhancement performance compared with other metal-free materials. The enhancement factors of the chiral nanostructures are 10 times more than that of achiral nanostructures for dye molecules (e.g., 22.5 times for crystal violet), indicative of significance of the chiral nanostructure to the macroscopic performance. Moreover, the superior reproducibility and generality of the PANI-based rose-like chiral nanostructures illustrate its high potential in Raman enhancement applications. This work not only provides an efficient metal-free platform for Raman enhancement but also develops herein the idea, which is highly instructive for the rational design of advanced Raman enhancement-active materials for broader applications.

A nanocomposite of silica coated magnetite nanoparticles and aniline-anthranilic acid co-polymeric nanorods with improved stability and selectivity for fluoroquinolones dispersive micro solid phase extraction

Adsorbents composed of polyaniline nanostructures or their derivatives immobilized on magnetic nanoparticles had gained increasing interest for application in dispersive micro-solid phase extraction. However, reproducible binding between polymeric PANI nanopaterials and magnetic nanomaterials are still a challenging task. Furthermore, other challenges are the enhancement of physical and chemical stability of adsorbent magnetic nanoparticles as well as improvement of polymeric PANI nanoparticles selectivity towards target analytes. This work described the reproducible preparation of a nanocomposite of aniline-anthranilic acid co-polymeric nanorods with silica coated magnetite nanoparticles by physical mixing of its basic components. The prepared nanocomposite had proven stability against chemical and atmospheric attack. The formed nanocomposite in this work had advantages regarding stability and selectivity towards fluoroquinolones as compared with analogues prepared from polyaniline polymers and/or uncoated magnetite nanoparticles. The selectivity of the formed adsorbent was further optimized for microextraction of four fluoroquinolone antibacterial agents. The application of the prepared nanocomposite was exemplified in microextraction of the studied fluoroquinolones from spiked milk samples to enable their detection down to their stated maximum residue limits.