Surface Morphology and Thermo-Electrical Energy Analysis of Polyaniline (PANI) Incorporated Cotton Fabric

With the exponential development in wearable electronics,a significant paradigm shift is observed from rigid electronics to flexible wearable devices.Polyaniline(PANI)is considered as a dominant material in this sector,as it is endowed with the optical properties of both metal and semiconductors.However,its widespread application got delineated because of its irregular rigid form,level of conductivity,and precise choice of solvents.Incorporating PANI in textile materials can generate promising functionality for wearable applications.This research work employed a straightforward in-situ chemical oxidative polymerization to synthesize PANI on Cotton fabric surfaces with varying dopant(HCl)concentrations.Pre-treatment using NaOH is implemented to improve the conductivity of the fabric surface by increasing the monomer absorption.This research explores the morphological and structural analysis employing SEM,FTIR and EDX.The surface resistivity was measured using a digital multimeter,and thermal stability is measured using TGA.Upon successful polymerization,a homogenous coating layer is observed.It is revealed that the simple pre-treatment technique significantly reduces the surface resistivity of Cotton fabric to 1.27 kΩ/cm with increasing acid concentration and thermal stability.The electro-thermal energy can also reach up to 38.2°C within 50 s with a deployed voltage of 15 V.The modified fabric is anticipated to be used in thermal regulation,supercapacitor,sensor,UV shielding,antimicrobial and other prospective functional applications.

RECTIFYING EFFECT OF POLYANILINE(PANI)/N-TYPE POROUS SILICONE HETEROJUNCTION

Heterojunctions between polyaniline (PANI) and n-type porous silicon (PS), Al/PS-PANI/Au cell, were fabricated, and the rectifying parameters of this heterojunction diode were measured as a function of the preparation conditions of PANI and PS, the electronic structure of PANI as well as cell structure. The rectifying parameters of Al/PS-PANI/Au cell were determined to be gamma = 1.8x10(1) similar to 1.0x10(5) for the rectifying ratio at 3V, n = 3 similar to 12 for the ideal factor, j(0) = 8.0x10(-5) similar to 5.6x10(-2) mA/cm(2) for the reversed saturated current density, and phi(0) = 0.67 similar to 0.83 V for the barrier height, respectively. The best rectifying heterojunction diode made between PANI and n-type PS with higher rectifying factor (gamma = 1.0x10(5) at 3V), output current (>1500 mA/cm(2) at 3V) and lower ideal factor (n = 3.3) was obtained by preventing the oxidation of PS before evaporating Al electrode.

Effect and mechanism of reductive polyaniline on the stability of nitrocellulose

The search for new green and efficient stabilizers is of great importance for the stabilization of nitrocellulose(NC). This is due to the shortcomings of traditional stabilizers, such as high toxicity. In this study, reduced polyaniline(r-PANI), which has a similar functional structure to diphenylamine(DPA) but is non-toxic, was prepared from PANI based on the action with N_(2)H_(4) and NH_(3)-H_(2)O, and used for the first time as a potential stabilizer for NC. XPS, FTIR, Raman, and SEM were used to characterize the reduced chemical structure and surface morphology of r-PANI. In addition, the effect of r-PANI on the stabilization of NC was characterized using DSC, VST, isothermal TG, and MMC. Thermal weight loss was reduced by 83% and 68% and gas pressure release by 75% and 49% compared to pure NC and NC&3%DPA, respectively.FTIR and XPS were used to characterize the structural changes of r-PANI before and after reaction with NO_(2). The 1535 cm^(-1) and 1341 cm^(-1) of the FTIR and the 404.98 eV and 406.05 eV of the XPS showed that the -NO_(2) was generated by the absorption of NO_(2). Furthermore, the quantum chemical calculation showed that NO_(2) was directly immobilized on r-PANI by forming -NO_(2) in the neighboring position of the benzene ring.

Conductivity Study of Polyaniline-Cobalt Ferrite(PANI-CoFe_2O_4) Nanocomposite

In this investigation,the structural and electrical properties of nanocomposites of polyaniline(PANI) and cobalt ferrite synthesized by hydrothermal route are reported for the first time(with weight ratios of CoFe_2O_4/PANI 1:2 and 2:1).Synthesized nanomaterials have been characterized by XRD,FT-IR,SEM and TEM techniques.FT-IR results confirm the presence of CoFe_2O_4 and PANI in the samples.Their detailed conductivity measurements have been investigated.It has been found that PANI has a more effective conducting mechanism in CoFe_2O_4-PANI composites.These results are also consistent with the change in AC conductivity orders in composites.

Simultaneous degradation of RhB and reduction of Cr(Ⅵ) by MIL-53(Fe)/Polyaniline(PANI) with the mediation of organic acid

MIL-53(Fe)/polyaniline(PANI) composite was prepared by in situ depositing PANI on the surface of MIL-53(Fe) and their catalytic performances on the simultaneous removal of Rh B and Cr(Ⅵ) were investigated. The elimination efficiency of both RhB and Cr(Ⅵ) reached more than 98% under pH = 2 where hydrochloric acid and citric acid were used to adjust the pH. The results indicated that MIL-53(Fe)/PANI revealed an obvious pH response to the degradation of RhB, while citric acid promoted the Cr(Ⅵ)photoreduction. UV–Vis spectra, EIS, and photocurrent response experiments showed that MIL-53(Fe)/PANI had a better light response and carrier migration ability than MIL-53(Fe). The transient absorption spectra also exhibited that the lifetimes of photo-generated carriers were prolonged after the conductive polymer deposition on the MIL-53(Fe) surface. Scavenger experiments demonstrated that the main active species were·O;-and·OH. Combined with activity evaluation results, and the possible photocatalytic mechanism of MIL-53(Fe)/PANI on RhB oxidation and Cr(Ⅵ) reduction was proposed. The addition of conductive polymer can effectively improve the light response of the catalyst under acidic conditions, and meanwhile citric acid also provided a new mediation for the synergistic degradation of multiple pollutants. Good activity and stability of the catalysts made the scale-up purification of acid water feasible under UV–Vis light.

Wet Chemical Synthesis of Entangled Nano-fibrous Conducting Polyaniline(PANI) Mesh: Effect of Heating and Stirring

An effect of heating and stirring in a facile wet chemical route to synthesize entangled nanofibrous mesh of doped polyaniline(PANI) was reported. The structural, morphological, and optical properties of PANI nano-fibers were found to be dependent on synthesis temperature and stirring. The XRD analysis confirms nano PANI formation with 2θ peaks around 15°, 21°, and 25° for(011),(020), and(200) crystal planes, respectively. The average crystallite size varies between 25 nm to 60 nm due to change in synthesis conditions. The SEM analysis reveals the clustered granule formation for PANI sample synthesized at 28 and 60 ℃ under continuous stirring, whereas, unstirred synthesis at 60 ℃ shows entangled nano-fibrous mesh morphology. The TGA study shows better thermal stability for PANI mesh over granular PANI. The FTIR spectra validates the emeraldine salt PANI formation with peaks corresponding to C-H, C-N, N=Q=N, N=B=N, and N-H vibration bands. The UV-Vis analysis shows the major absorbance peaks around λ: 340 nm(π-π* transition of benzenoid ring), and λ: 800 nm(π-π*, polaron-π*, π-polaron transitions). The dense entangled nano-fibrous coating of PANI synthesized at 60 ℃ without stirring shows highest electrical conductivity of 3.79 S·cm^-1.

Development of a Novel Reusable Real Time Monitoring Glucose Sensor Based on Nanostructured Conducting Polyaniline (NSPANI)

A novel mediatorless reusable glucose biosensor with a remarkable shelf life has been fabricated on electrodeposited film of chemically synthesized nanostructured polyaniline (NSPANI) on indium tin oxide (ITO) coated glass plates using cyclic voltammetry. Glucose oxidase has been covalently immobilized on electrodeposited NSPANI film to fabricate a glucose bioelectrode (GOx/NSPANI-SDS/ITO). The results of linear sweep voltammetry and the high value of heterogeneous rate constant as obtained using Laviron equation indicates that GOx/NSPANI-SDS/ITO bioelectrode can detect glucose in the range of 0.5 to 10.00 mM with high sensitivity of 13.9 μA?mM?1 with a fast response time of 12 seconds. The linear regression analysis of bioelectrode reveals standard deviation and correlation coefficient of 6 μA and 0.994, respectively. The low value of Michaelis-Menten constant (Km) estimated as 0.28 mM using Lineweaver-Burke plot indicates high affinity of glucose oxidase enzyme to glucose and transfer rate. The GOx/NSPANI-SDS/ITO bioelectrode exhibits uniform activity for 12 weeks under refrigerated conditions;however the study is further going on. Attempts have been made to utilize this electrode for estimation of glucose in blood serum and results are found to be within 11% error. The unique features of this novel electrode lie on its reusability, real time monitoring, reproducibility and remarkable shelf life apart from the wide linear range, high sensitivity, low Km value, high heterogeneous electron-transfer constant etc.

Synthesis of Chiral Polyaniline Induced by Modified Hemoglobin

The synthesis of chiral polyaniline （PANI） induced by modified hemoglobin （Hb） was pro- foundly explored for the first time. Results revealed that after being separated, inactivated or immobilized, Hb can still induce the formation of chiral PANI successfully, suggesting that Hb can be used as the chiral inducers regardless of harsh reaction conditions. By examining the properties of PANI induced by modified Hb, it was found that Hb（inactivated）-PANI possessed excellent chirality, stability, and crystalline structure. The globin separated from Hb was demonstrated to have the ability of inducing the production of chiral PANI whereas the hematin from Hb had no capacity to direct enantio specificity for the PANI chains. Results indicated that Hb（immobilized）-PANI exhibited poor yield, doping state, and crys- talline structure, indicating that the immobilization of Hb by entrapment was not beneficial to the polymerization reaction. Results also showed that the structure of Hb may have significant effects on the morphologies of chiral PANI.

PREPARATION OF POLYANILINE/ACETYLENE BLACK COMPOSITE AS HOLE CONDUCTOR IN SOLID-STATE DYE-SENSITIZED SOLAR CELL

A clay-like conductive material comprising polyaniline（PANI）-acetylene black particles is fabricated as a hole conductor for dye sensitized solar cell（DSSC）.The results show that the introduction of acetylene black into the polymer electrolyte improves the photovoltaic behavior of solid-state DSSC,owing to the increase of the hole mobility of PANI electrolyte,the improvement of the wetting quality of the composite electrolyte,and the reinforcement of interface contact between electrode and the electrolyte.Finally,the overall energy conversion efficiency of DSSC with PANI-50%（in weight）acetylene black electrolyte is 48% of that of liquid DSSC.Therefore,the PANI-acetylene black composition is a credible alternative to hole conductor in application of solid DSSC.

rGO/PANI对Cr(Ⅵ)的吸附还原性能及机理分析

以还原氧化石墨烯(rGO)为载体,采用原位聚合法将聚苯胺(PANI)负载到rGO上以增大其比表面积,探究复合材料对溶液中Cr(Ⅵ)的吸附还原反应效果。采用SEM、XRD、BET、FTIR和XPS等对rGO/PANI复合材料进行表征,从吸附等温模型、吸附动力模型等角度探讨rGO/PANI对Cr(Ⅵ)的吸附还原反应特征及机理。结果表明,rGO/PANI对Cr(Ⅵ)的去除包括吸附、络合和还原三个部分。Cr(Ⅵ)一部分吸附在rGO/PANI表面,一部分还原成Cr(Ⅲ),还原的Cr(Ⅲ)部分被络合在复合材料表面,少量扩散到溶液中。在pH=2时,rGO/PANI对Cr(Ⅵ)的最大去除量可达到97.61 mg/g,其中,吸附还原量为73.46 mg/g,溶液中剩余的Cr(Ⅲ)浓度为24.13 mg/L。

Palladium nanoparticles in cross-linked polyaniline as highly efficient catalysts for Suzuki-Miyaura reactions

Palladium nanoparticles supported on cross-linked polyaniline with bulky phosphorus ligands were developed.These catalysts showed high efficiency in the Suzuki-Miyaura reaction of aryl chlorides and bromides with phenylboronic acids.Aryl chlorides and bromides with functional groups,such as CN,MeO,CHO,MeCO and NO_2,were converted to the corresponding biphenyls in high yields with catalyst loading.Additionally,the catalysts combined high activity with good reusability;they could be used at least five times for the Suzuki-Miyaura coupling reaction.

Fe^(3+)/Fe^(2+) redox electrolyte for high-performance polyaniline/SnO_2 supercapacitors

The Fe3＋/Fe2＋ redox electrolyte for use in polyaniline/tin oxide （PANI/SnO2）supercapacitors was reported. The influences of redox electrolyte based on different Fe3＋/Fe2＋ ion pair concentrations in 1 mol/LH2SO4 solution on the pseudocapacitive behaviors of PANI/SnO2 supercapacitor were investigated. The electrochemical properties of the supercapacitor were studied by cyclic voltammetry （CV）, galvanostatic charge discharge （GCD）, and electrochemical impedance spectroscopy （EIS） techniques. It is found that the performance of the supercapacitor is the best when the Fe3＋/Fe2＋ concentrationis 0.4 mol/L and its initial specific capacitance is 1172 F/g at an applied current density of 1 A/g. The long-term cycling experiment shows good stability with the retention of initial capacitance values of 88% after 2000 galvanostatic cycles. The experimental results testify that using Fe3＋/Fe2＋ redox electrolyte has a good prospect for improving the performances of energy-storage devices.

Electrochemical Behavior and Specific Capacitance of Polyaniline/Silver Nanoparticle/Multi-walled Carbon Nanotube Composites

In this work, we fabricated the polyaniline/silver nanoparticle/multi-walled carbon nanotube （PANI/Ag/MWCNT） composites by in situ polymerization of aniline on the wall of Ag/MWCNTs with different aniline to Ag/MWCNT mass ratios. The chemical structure of the ternary composites was characterized by Fourier transform infrared spectroscopy, Xray diffraction, and X-ray photoelectron spectroscopy. Scanning electron microscope and high-resolution transmission electron microscopy were used to observe the morphology of the ternary composites. The results showed that the polyaniline PANI layer was prepared successfully and it covered Ag/MWCNTs completely. In addition, Ag nanoparticles between the MWCNT core and the PANI layer existed in the form of elemental crystal, which could contribute to the electrochemical performance of the composites. Then we prepared the composite electrodes and studied their electrochemical behaviors in 1 mol/L KOH. It was found that these composite electrodes had very low impedance, and exhibited lower resistance, higher electrochemical activity, and better cyclic stability compared with pure PANI electrode. Particularly, when the mass ratio of aniline to Ag/MWCNTs was 5：5, the composite electrode displayed a small equivalent series resistance （0.23 Ω） and low interfacial charge transfer resistance （〈0.25 Ω）, as well as 160 F/g of the maximum specific capacitance at a current density of 0.25 A/g in KOH solution. We could conclude that the composite material had potential applications as cathode materials for lithium batteries and supercapacitors.

Antibacterial Effect of the Conducting Polyaniline

Excellent antibacterial performance of polyaniline （PAni） against Escherichia coli and Gram-positive Staphylococcus aureus microorganisms has been demonstrated under both dark and visible light conditions. The electrostatic adherence between the PAni molecules and the bacteria may play a very important role for the antibacterial reaction of the PAni. As a result of our investigation, conducting PAni and its composites/blends are believed to be useful as a new type of antibacterial agent, self-clean as well as multifunctional material for improving the human health and living environment.

A novel polyaniline/mesoporous carbon nano-composite electrode for asymmetric supercapacitor

A novel nano-composite of polyaniline/mesoporous carbon（PANI/CMK-3） was prepared with mesoporous carbon（CMK-3） serving as the support.Electrochemical asymmetric capacitors have been successfully designed by using PANI/CMK-3 composite and CMK-3 as positive and negative electrode,respectively.The results showed that the discharge capacity of the asymmetric capacitor could reach 87.4 F/g under the current density of 5 mA/cm^2 and cell voltage of 1.4 V.The energy density of the asymmetric capacitor was up to 23.8 Wh/kg with a power density of 206 W/kg.Furthermore,PANI/CMK-3-CMK-3 asymmetric capacitor using this PANI/CMK-3 nano-composite could be activated quickly and possess high charge-discharge efficiency.

WO_(3)@PANI复合材料的制备及其pH传感性能

目的通过简单快捷的方法制备氧化钨(WO_(3))/聚苯胺(PANI)复合材料,获得高性能pH传感器。方法WO_(3)和PANI都是通过原位聚合法制备,在溶液中混合后旋涂在柔性碳基底上。通过扫描电子显微镜、拉曼光谱、XRD等技术对复合材料进行表征,证明复合材料的成功合成并进一步解释其传感增强原理。结果WO_(3)@PANI可以在pH=2~10内工作,与单体材料相比具有较高的灵敏度(-53.13 mV),较低的滞后度(3.8%)和较快的反应速度(16 s),在10次酸碱循环测试后响应性保持在95%以上,且在12 h的连续测试中可以保持稳定。结论一方面PANI为WO_(3)提供了导电网络,并将WO_(3)均匀包裹在内;另一方面两者的p-n结构共同作用,使得WO_(3)@PANI的pH传感性能进一步提高。

Platinum-polyaniline-modified carbon fiber electrode for the electrooxidation of methanol

Platinum was electrodeposited onto a polyaniline-modified carbon fiberelectrode by the cyclic voltammetric method in sulfuric acid, which may enable an increase in thelevel of platinum utilization currently achieved in electrocatalytic systems. This electrodepreparation consists of a two-step procedure: first electropolymerization of aniline onto carbonfiber and then electrodeposition of platinum. The catalytic activity of theplatinum-polyanihne-modified carbon fiber electrode (Pt/PAni/C) was compared with that of a barecarbon fiber electrode (Pt/C) by the oxidation of methanol. The maximum oxidation current ofmethanol on Pt/PAni/C is 50.7 mA centre dot cm^(-2), which is 6.7 times higher than 7.6 mA centredot cm^(-2) on the Pt/C. Scanning electron microscopy was used to investigate the dispersion of theplatinum particles of about 0.4 um.

A flexible solid-state supercapacitor based on graphene/polyaniline paper electrodes

The direct coating of graphene sheets obtained by electrochemical exfoliation on commercial paper renders the preparation of highly conductive flexible paper substrate for subsequent deposition of polyaniline (PANi) nanorods via electrochemical polymerization. The deposit ion of PANi can be well-controlled by adjusting the electrochemical polymerization time, leading to the formation of PANi coated graphene paper (PANi-GP). The as-prepared electrode exhibited high areal capacitance of 176 mF cm^-2 in three-electrode system at a current density of 0.2 mA cm^-2 which is around 10 times larger than that of pris-tine graphene paper due to the pseudocapacitive behavior of PANi. In-situ Raman test was used to determine the molecular changes during redox process of PANi. More importantly, all-solid-state symmetric capacitor assembled with two PANi-GP electrodes in a polymer electrolyte delivered an areal capacitanee of 123 mF cm^-2, corresponding to an areal energy density of 17.1 μWh cm^-2 and an areal power density of 0.25 mW cm^-2. The symmetric capacitor held a capacitive retention of 74.8% after 500 bending tests from 0 to 120°, suggesting the good flexibility and mechanical stability. These results showed the great promising application in flexible energy-storage devices.

A Novel Immunosensor Based on Au Nanoparticles and Polyaniline/Multiwall Carbon Nanotubes/Chitosan Nanocomposite Film Functionalized Interface

A novel multilayer film based on Au nanoparticles(AuNPs) and polyaniline/carboxylated multiwall carbon nanotubes-chitosan nanocomposite(PANI/MWCNTs/CS) was exploited to fabricate a highly sensitive immunosensor for detecting chlorpyrifos. PANI-coated MWCNTs were prepared by in situ chemical polymerization and carboxylated MWCNTs played an important role in obtaining the thin and uniform coating of PANI resulting in the improved immunosensor response. Au NPs were used as a linker to immobilize chlorpyrifos antibody. The performance of the immunosensor was characterized by means of cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM), respectively. All variables involved in the preparation process and analytical performance of the immunosensor were optimized.Under optimal conditions(antibody concentration: 5 μg/mL, working buffer pH: 6.5, incubation time: 40 min,incubation temperature: 25℃), the immunosensor exhibited a wide linear range from 0.1 to 40× 10^(-6)mg/mL and from 40 × 10^(-6)mg/mL to 500 × 10^(-6)mg/mL, and with a detection limit of 0.06 × 10^(-6)mg/mL, which provided a valuable tool for the chlorpyrifos detection in real samples.