Graphene Oxide Polyaniline Research Articles

Structural, optical and electrochemical properties of reduced graphene oxide-polyaniline composites for supercapacitor applications

Structural, optical and electrochemical properties of reduced graphene oxide-polyaniline composites for supercapacitor applications

Polyaniline/graphene oxide nanocomposite as an innovative cathode for high energy density aqueous zinc-ion batteries

In order to resolve hard processability, poor conductive and lower capacity of polyaniline(PANI), We design and obtain a nanofiber network polyaniline/graphene oxide(PGO) and polyaniline/graphene oxide/manganese dioxide(PMGO) composite cathode. They are synthesized by electrochemical in-situ intercalative polymerization on oxidized graphite paper and assembled with the zinc anode into aqueous Zn-ion batteries(AZIBs). The initial discharged specific capacity of the PGO cathode is 224 mAh·g-1, and it is lower than that of the PMGO electrode when it discharges at 200mA·g-1. However, the capacity can reach 345 mAh·g-1 with better stability and reversibility compared to the PMGO under the same discharge/charge conditions. Characterization analysis and electrochemical studies show that the PGO composite cathode provides a large specific surface and charge/discharge channel, which optimizes the electrochemical performance of the battery. We also propose a new energy storage mechanism for intercalating PANI into graphene oxide(GO) layers to construct a nano-three-dimensional(3D) network for AZIBs and a proton pool with a hydrogen bond network of the PGO electrode. It is profitable for hindering the polarization, facilitating the electrode reaction, and enhancing the capacity and stability. For these reasons, the storage performance of the PGO electrode is superior to the polyaniline cathode reported at present.

Removal of anionic dye from textile effluent using zirconium phosphate loaded polyaniline-graphene oxide composite: Lab to pilot scale evaluation

Efficient filtering of dyes is essential for the protection of ecosystem and human health due to the considerable water pollution caused by the effluents released from the sector. We present a simple, scalable UV radiation-assisted method for treating methyl orange dye-polluted water from the textile industry using zirconium phosphate-loaded polyaniline-graphene oxide (PGZrP) composite. The new material was synthesized by sonochemically incorporating a polyaniline-graphene oxide composite with hydrothermally synthesized zirconium phosphate. The efficacy of PGZrP in eliminating methyl orange was evaluated using experimental conditions, and the adsorption capacity was investigated as a function of pH, temperature, adsorbent dosage, and adsorption period. The system follows Langmuir adsorption isotherm with pseudo-second-order kinetics. Thermodynamics studies showed that enthalpy (H°) and entropy (S°) values are positive, indicating that the dye adsorption increases with increasing temperature and is an endothermic reaction. The maximum adsorption capacity was found to be 36.45379 mg/g for methyl orange. Using the COMSOL Multiphysics CFD Platform, an attempt was made to check the temperature and concentration profile of a PGZrP composite in a real industrial system. The predicted result shows that there is no significant temperature change in the material during the adsorption process and the concentration of dye is mainly located on the top region of the bed. The developed zirconium phosphate decorated polyaniline-graphene oxide composite can be successfully utilized for the effective removal of methyl orange from industrial wastewater in bulk quantity which is coming from the textile industry, and the composite can be reused for several cycles with good efficiency. In this work, we have designed a miniaturized proof of concept to remove methyl orange from water which showed good dye removal efficiency.

Effect of Graphene Oxide Addition on the Properties of Electrochemically Synthesized Polyaniline-Graphene Oxide Films.

In this work, the electrochemical synthesis of PANI and GO-modified PANI was performed using cyclic voltammetry, varying the amount of GO, 1 mg (PG1), 5 mg (PG5), and 10 mg (PG10) to analyze the effect of the amount of GO on the composite. PANI, PG1, PG5, and PG10 materials were characterized using optical microscopy, SEM, UV-vis, FTIR, Raman, and wettability. A stability test was also carried out by putting the materials to 500 oxidation-reduction cycles using cyclic voltammetry. The synthesis method allowed GO in PANI to be added through a chemical interaction between the two compounds. It was also found that the addition of GO led to an improvement in the hydrophilic character of the composite, which would lead to an improvement in the diffusion of reagents/species when the composites are used in aqueous media processes. The results of the stability test showed that the PG10 material presented a lower % loss of specific capacitance and energy compared with the other materials, which indicates that the GO presence (in the amount specified) improves the stability of the PANI. The PG10 material showed favorable and promising conditions for its use in fuel cell and battery processes.

Simulation performance of inkjet-printed polyaniline–graphene oxide nanocomposite based gas sensor

Simulation performance of inkjet-printed polyaniline–graphene oxide nanocomposite based gas sensor

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.

Temperature-induced photoluminescence amplification of graphene oxide-polyaniline composite through interaction modulated charge transfer

This report plies the effect of temperature on the interaction of GO and polyaniline at different pH through photoluminescence (PL) studies. At neutral pH, the interaction of GO-PANI is found to be highly temperature-dependent. A ground state charge transfer (CT) from the polaronic state of PANI to the GO remained at the backbone of the photophysics. The electron transfer from PANI to GO becomes more significant at a higher temperature because of the better interaction of GO with PANI moiety through π−π stacking and hydrogen bonding. The CT-induced PL amplification at elevated temperature is originating from the recombination of the spatially separated electron in the excited state of GO and hole in the PANI. The thermodynamic parameters ΔH and ΔS have been calculated associated with the electron transfer process. The positive change in the electronic entropy due to the better delocalization overcomes the entropy change due to structural orderness that drives the electron transfer process. The intensity of different PL bands remains unaffected by the temperature at lower pH due to saturated electron transfer and lower GO-PANI interaction, whereas at higher pH the CT PL band intensity decreases with an increment in temperature, explained by the increase in GO-PANI distance.

Effect of modified titanium dioxide photoanode and agarose gel electrolyte on electrochemical studies of dye-sensitized solar cell

Recently, the study of new DSSC structures such as photoanodes, electrolytes, and counter electrodes (CE) have gained the attention of researchers. Combining these features allows DSSC to have a flexible and versatile way of working. Titanium dioxide-graphene (TiO2-G) nanocomposite containing 3 wt % graphene (G) was successfully fabricated and employed as the photoanode for the fabrication of a dye-sensitized solar cell (DSSC). Agarose (3 wt %) together with potassium iodide (KI) were prepared as gel electrolytes and polyaniline-graphene oxide (PANI-GO) served as the counter electrode (CE). In UV–visible spectroscopy, doping of graphene on TiO2 led to a remarkable reduction of the band gap energy from 3.0 eV (TiO2) to 2.4 eV (TiO2-G). The presence of agarose in the KI solution facilitated the creation of fine channels, promoting ionic transfer in electrolytes, as revealed by field emission scanning electron microscopy (FESEM). Moreover, the current-voltage (I–V) curve for TiO2-G/3 wt % agarose gel electrolyte/PANI-GO demonstrated a power conversion efficiency (PCE) value of 1.1324% with optimal values for short circuit current density (JSC), open circuit voltage (VOC), and fill factor (FF) of 34.48 mA/cm2, 0.1105 V, and 0.2972, respectively. Cyclic voltammetry (CV) illustrated redox potential occurrences at −0.2 V and +0.2 V, corresponding to oxidation and reduction processes, confirming the chemical stability of DSSC. The system demonstrated stability after 10 cycles, maintaining consistent current (μA) and voltage (V) patterns even after 20 cycles. These results demonstrate the efficient and cost-effective DSSC system's capacity to maintain stability and guarantee consistent energy conversion.

A novel electrochemical aptasensor based on AuNPs-loaded graphene oxide-polyaniline for sensitive detection of aflatoxin B1

A novel electrochemical aptasensor based on AuNPs-loaded graphene oxide-polyaniline for sensitive detection of aflatoxin B1

Reduced graphene oxide-polyaniline hybrid nanocomposite for selective sensing of ammonia gas at room temperature

A binary solvent system (DMSO + water) assisted swollen liquid crystalline lamellar mesophase (SLCLM) template is effectively used to produce the reduced graphene oxide-polyaniline (rGO-PANI) nanocomposite. The large surface area and 2D hybrid nanosheets of PANI and rGO collectively persuade, providing an anchor for the ammonia gas sensing process. The obtained gas sensing results demonstrate the synthesized rGO-PANI films exhibited the highest gas sensitivity, excellent repeatability, good linear gas concentration response, a low detection limit (200–1000 ppb), and an ultrahigh sensitivity of 32 %. The newly synthesized morphology of rGO-PANI nanocomposite may be one of the factors for the enhanced NH3 gas response. All characterization techniques, such as XRD, HR-TEM, XPS, FT-IR, and Raman spectroscopy, confirm the formation of the rGO-PANI hybrid nanocomposite. Furthermore, the NH3 gas sensitivity in the relative humidity range of 34 %–57 % showed only ∼1 % variation. The development of 2D nanosheets of hybrid rGO-PANI nanocomposite in SLCLM with enhanced gas sensing properties is significant for the future development of selective and sensitive RT ammonia sensors.

A detailed molecular dynamics simulation and experimental investigation of CO2 adsorption on graphene oxide-polyaniline nanocomposite

The study investigated the sorption and diffusion of carbon dioxide on Graphene oxide-polyaniline (GO-PANI) using volumetric method and molecular dynamics simulations. The experimental results showed that GO-PANI was more effective at adsorbing CO2 than either of the individual materials alone. Simulations supported this trend in CO2 adsorption and provided additional insights into the structural information of the adsorbents and the dynamics of CO2 molecules. The Langmuir adsorption model was employed to fit sorption isotherms computed using Grand Canonical Monte Carlo (GCMC) method. The GO-PANI nanocomposite compound exhibited a superior adsorption rate compared to pure structures. The isosteric heat for CO2 adsorption was 27.59 kJ/mol. The interaction energy of single molecules of CO2 on GO-PANI surface was −38.075 kcal/mol. Diffusion coefficient value for CO2 was 41.2 × 10 −9 m2/s, lower than that of the pure polymer. FT-IR, FE-SEM, and BET techniques were used to analyze synthesized GO-PANI structure. The highest CO2 adsorption was observed at a temperature of 283 K. Isosteric heat adsorption decreased with uniform surface charge. This research provides critical microscopic information on gas adsorption in polymer nanocomposites and demonstrates the effectiveness of GO-PANI as an efficient adsorbent for carbon dioxide, which could be useful in various industrial applications.

Synthesis Of Graphene Oxide Modified Polyaniline And Its Electrochemical Application For Detection of Nitric Oxide

Nitric oxide plays a crucial and important role in cellular physiology and also functions as a human cancer signaling molecule. Nitric oxide (NO) also exhibits antimicrobial and antitumor properties. However, conventional detection methods have their own limitations in the detection of NO at low concentrations because of its high reactivity and low lifetime. Here, we report a strategy to graphene oxide (GO)-modified polyaniline with efficiency to detect NO at a low concentration by electrocatalytic method. For this study we prepared graphene oxide polyaniline (GO-PANI) which has higher stability and stronger catalytic activity towards the oxidation of nitric oxide (NO).The synthesized compound was characterized by field emission scanning electron microscopy (FESEM) and UV-visible spectroscopy. With further modification of Nafion, the determination of NO in PBS with different concentration .This investigation offers a different method for determination of NO.

Composite nanoarchitectonics with reduced-graphene oxide and polyaniline for a highly responsive and selective sensing of methanol vapors

In an approach to develop room temperature, highly responsive and selective methanol gas sensor, reduced graphene oxide-polyaniline nanocomposites have been successfully synthesized through simple chemistry based chemical oxidative synthesis process in the presence of camphor sulfonic acid. Field emission scanning electron microscopy, Raman spectroscopy, and X-ray diffraction, respectively, were used to examine the morphological, vibrational, and structural characteristics of synthesized samples systematically. The morphology of prepared samples was observed as nanoparticles and structure as semi-crystalline in nature. Raman spectra of synthesized samples exhibit all essential bands that confirm the growth of expected samples. Thereafter, these samples were studied as sensors for the detection of 50, 100, 150 and 200 ppm levels of methanol vapors. It was found that 8 wt% reduced graphene oxide doped polyaniline composite exhibits the highest response (%) i.e., 52% at 200 ppm. Furthermore, these sample showed good stability even after 180 days of fabrications. To understand the response of these composites, a sensing mechanism is also discussed. Our results shows that reduced graphene oxide doped polyaniline-based gas sensors showed high response, selectively towards Methanol vapors. Moreover, prepared sensors showed appreciable stability, reproducibility and repeatability making them suitable candidates for commercial production of methanol vapor sensors.

Zirconium Phosphate-Incorporated Polyaniline-Graphene Oxide Composite Modified Electrodes for Effective and Selective Detection of Nitrite.

Nitrite contamination in food, water, and environmental samples poses a substantial health hazard, owing to its capacity for transformation into carcinogenic compounds. Given the profound ecological and physiological implications, precise and highly sensitive surveillance of nitrite has emerged as an imperative area of concern, addressing the substantial detrimental impact that it can have on both terrestrial and aquatic ecosystems. The novel electroactive polyaniline-graphene oxide composite, incorporating hexagonal zirconium phosphate discs (PGZrP), was systematically engineered as a foundation for an advanced electrochemical sensor, enabling precise nitrite detection in diverse aqueous and biological matrices. At a specific potential peak of +0.85 V, observed within a pH 7.0 phosphate buffer solution, the PGZrP-modified glassy carbon electrode (GCE) exhibited exceptional electrocatalytic proficiency in the sensing nitrite ions (NO2-), surpassing the performance of alternative electrode configurations, including the zirconium phosphate-modified GCE (ZrP/GCE), graphene oxide-modified GCE (GO/GCE), polyaniline-graphene oxide-modified GCE (PG/GCE), and the unmodified bare glassy carbon electrode. The constructed sensor demonstrated an impressive limit of detection at 80 nM along with a broad and linear detection range spanning from 124 nM to 40 mM. The synergistic effect created by the close contact between ZrP and PG, which resulted in a well-enhanced electrochemical sensing capability, was responsible for this exceptional activity. The developed sensor exhibited an enhanced electrochemical performance characterized by an extended operational range, a heightened detection threshold, and exceptional sensitivity. The PGZrP/GCE sensor, as fabricated, consistently demonstrated commendable operational stability, robust reproducibility, and remarkable repeatability in its capacity for nitrite detection. Furthermore, its successful application in the precise quantification of nitrite levels within environmental water samples and blood specimens showcased an impressive recovery rate, establishing it as a promising tool for diverse analytical applications. These findings indicate the promising potential of the PGZrP composite for integration into electrochemical devices designed to deliver rapid response times, heightened sensitivity, and sustained stability, thereby placing it as a potential candidate for the production of cutting-edge sensors, particularly those employed for the precise recognition of nitrite in aquatic and biological specimens.

Polyaniline/carbon hybrids: Synthesis and application for alizarin red S removal from water

Polyaniline (PANI) nanofibers, Polyaniline/graphene oxide (PANI/GO) and polyaniline/carbon nanotube (PANI/CNTs) hybrids have been successfully prepared as highly effective adsorbent materials to remove alizarin red S (AR) dye from water. Herein, PANI nanofibers, PANI/GO composites, and PANI/CNTs composites were synthesized by chemical oxidation, directly blending, and in-situ polymerization methods, respectively. Compared with the mono-component PANI and carbon materials (GO, CNTs), the obtained PANI/carbon hybrid materials exhibited superior adsorption ability towards AR due to the synergistic effect. Effects of adsorption condition (i.e. adsorbents dosage, temperature, solution pH, adsorption time and the initial AR concentration) on the adsorption ability of the adsorbents were systematically studied. The sorption kinetics and isotherms of the hybrids for AR adsorption were studied with different models. Moreover, the adsorption ability of the PANI/carbon material hybrids towards other dye molecules, as well as their desorption and regeneration were also explored.

Synthesis of polyaniline-graphene oxide based ternary nanocomposite for supercapacitor application

This study focuses on the synthesis of Polyaniline (PANI), graphene oxide (GO), and their nanocomposites with metal oxides (MO) and hexagonal boron nitride (h-BN) for their application in the supercapacitor. In this study, PANI/GO, PANI/GO/TiO2, PANI/GO/MoS2 and PANI/GO/h-BN ternary nanocomposites were synthesized following a chemical oxidative polymerization method. The prepared nanocomposites were characterized by FTIR, XRD, TGA, SEM and electrochemical analysis. The electrochemical properties of the nanocomposites were evaluated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), electrochemical polarization and impedance analysis. CV profile of the nanocomposite showed that incorporation of GO, MO and h-BN in the polyaniline backbone improved capacitance, energy density and power density significantly. Among the synthesized ternary nanocomposites, PANI/GO/h-BN showed highest capacitance of 946 F/g and high capacitance retention after 100 cycles of charging and discharging. Finally, a set of hybrid asymmetric supercapacitors were constructed using the synthesized nanocomposites as positive electrode and activated carbon as negative electrode. The device was assessed following the GCD method. The supercapacitor device with PANI/GO/h-BN nanocomposite as positive electrode exhibited higher specific capacitance of 351 F/g with high power density of 4500 W/kg, and it lit up a 5 mm LED for 243 min, indicating its superiority over other electrodes.

Polyaniline–Graphene Oxide Composites Decorated with ZrO2 Nanoparticles for Use in Screen-Printed Electrodes for Real-Time l-Tyrosine Sensing

Polyaniline–Graphene Oxide Composites Decorated with ZrO₂ Nanoparticles for Use in Screen-Printed Electrodes for Real-Time <scp>l</scp>-Tyrosine Sensing

Nitrogen-doped reduced graphene oxide-polyaniline composite materials: hydrothermal treatment, characterisation and supercapacitive properties

High-temperature treatment increased the conductivity, carrier density and mobility of N-RGO. Inclusion of PANI tailored activities from capacitive to battery-like and diffusion-controlled.

Shearing induced ordered structures in two-dimensional nanomaterials-based electrodes for boosted pseudocapacitive kinetics

Two-dimensional (2D) nanomaterials have been extensively pursued as functional electrodes in electrochemical energy storage devices. Numerous efforts have been devoted to improving the electrochemical performance by engineering the chemical composition and structure of 2D nanomaterials, while little attention was paid to optimizing their electrode manufacturing by wet processing techniques. Herein, we study how the shear processing impacts the electrochemical performance of 2D nanomaterial-based electrodes using graphene oxide/polyaniline (GO/PANI) colloidal hydrogels as a model electrode slurry. The GO/PANI hydrogels are processed into reduced GO/PANI (RGO/PANI) membranes by blade casting followed by chemical reduction. The formation process and microstructure of the RGO/PANI membranes were revealed by rheology and synchrotron small-angle X-ray scattering. We find that a high shear rate in blade casting is favourable for inducing ordered alignment of the 2D nanosheet-like network structure of GO/PANI hydrogels, leading to the formation of stratified microstructure in the RGO/PANI membranes. The high shear-induced ordered structures greatly boost the pseudocapacitive kinetics of RGO/PANI membranes as flexible supercapacitor electrodes. Our findings highlight the significance of electrode processing of 2D nanomaterials for large-scale manufacturing for future industrial applications.

Novel anticorrosive coating of silicone acrylic resin modified by graphene oxide and polyaniline

Abstract Coatings of metal surfaces is a convenient and low cost anti-corrosion issue, while corresponding defects like poor heat and corrosion resistance are also obviously hinder its further application. Hence, continuously developing new and efficient coatings is of great significance to improve anti-corrosion for metals. In this study, silicone-acrylic resin was modified by two-dimensional lamellar structure of graphene oxide (GO) though direct co-blending to improve the anti-corrosion. Then, polyaniline/graphene oxide (PANI/GO) composites was prepared by in-situ polymerization method, which innovatively achieved the combination of flake and fibrous materials to fill the voids generated when the coating is cured into a film, and enhance the density and the anti-corrosion performance of the coating. The result showed that the coating modified by PANI/GO had the better thermal stability, which T 5% and T max are increased by 44 and 5 °C, respectively. Electrochemical impedance spectroscopy (EIS) and Tafel polarization curves were employed to analyze anticorrosion performance of modified coatings explored in 3.5 wt% NaCl aqueous solution. The coating with 20 wt% GO in PANI/GO has the best corrosion resistance with corrosion potential of −0.14 (V vs. Hg/Hg2Cl2), corrosion current density of 1.8 × 10−11 A cm−2, polarization resistance of 6.06 × 1010 Ω cm2, and lower corrosion rate of 4.18 × 10−7 mm year−1 after immersion for 60 day.