Polyaniline Composite Thin Films Research Articles

Highly Sensitive and Selective Sol-Gel Spin-Coated Composite TiO2–PANI Thin Films for EGFET-pH Sensor

A highly selective and sensitive EGFET-pH sensor based on composite TiO2-PANI had been developed in this work. A sol-gel titanium dioxide (TiO2) and the composite of TiO2 with semiconducting polyaniline (PANI) were deposited using a simple spin-coating method on an indium tin oxide (ITO) substrate. The films have been explored as a sensing electrode (SE) of extended gate field-effect transistor (EGFET) for pH applications in the range of pH 2 to 12. The pH sensitivities between TiO2, TiO2-PANI bilayer composite, and TiO2-PANI composite thin films were discussed. Among these, the TiO2-PANI composite thin film showed a super-Nernstian behavior with high sensitivity of 66.1 mV/pH and linearity of 0.9931; good repeatability with a standard deviation of 0.49%; a low hysteresis value of 3 mV; and drift rates of 4.96, 5.54, and 3.32 mV/h in pH 4, 7, and 10, respectively, for 6 h. Upon applying the TiO2-PANI composite as the SE for nitrate measurement, low sensitivity of 12.9 mV/dec was obtained, indicating that this film is a highly selective sensing electrode as a pH sensor. The surface morphology and crystallinity of the thin films were also discussed.

Investigating the Structure and Properties of Polyaniline Composite Thin Films

Investigating the Structure and Properties of Polyaniline Composite Thin Films

Structural, Optical and Thermal Properties of PVC/ Polyaniline Composite Thin Films

Structural, Optical and Thermal Properties of PVC/ Polyaniline Composite Thin Films

Development of Porous Manganese Oxide/Polyaniline Composite Using Electrochemical Route for Electrochemical Supercapacitor

Manganese oxide (MnO2)/polyaniline composite thin films were deposited using the electrochemical route for the fabrication of supercapacitor devices. The MnO2 polyaniline composite was prepared with different percentages of MnO2 and polyaniline and its structural, morphological, electrochemical, wettability and supercapacitor properties have been studied. The effects of the different percentages of MnO2 and polyaniline on the supercapacitor have been investigated. The thin film containing 80% polyaniline and 20% MnO2 shows relatively better supercapacitance, i.e., 409 F/g as compared to other composite thin films. The same film shows the retention of 92% of its original specific capacitance value after 1000 cycles. Similarly, after 2000 cycles, this value is still 84%.

The investigation of reduced graphene oxide@ SnO2–polyaniline composite thin films for ammonia detection at room temperature

The reduced graphene oxide@ SnO2 (GS)–polyaniline (PANI) composite was synthesized through the in situ chemical oxide polymerization for ammonia (NH3) gas detection at room temperature. The structure and morphology of resultant GS–PANI composite were characterized by ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and field emission scanning electron microscopy, respectively. The NH3 sensing performance of the composite was investigated and compared with that of the sensors based on bare PANI and GS. The results revealed that the GS–PANI composite film exhibited 160 % response (1.4 and 16 times response enhanced) to 20 ppm NH3 than that of bare PANI and GS based devices. Meanwhile, the GS–PANI based sensors displayed linearity in response and homogeneous repeatability on exposure to NH3 at room temperature.

Optical and Structural Properties of Solution-Processed Polyaniline Composite Thin Films with C<SUB>60</SUB> and Multi Wall Nanotube

Optical and Structural Properties of Solution-Processed Polyaniline Composite Thin Films with C<SUB>60</SUB> and Multi Wall Nanotube

Structural and electrical studies on PVDF:PANI composite thin films and their application as buffer layer on hybrid solar cells

Hybrid (organic–inorganic) solar cells were fabricated and tested using buffer layer of polyaniline (PANI)–poly(vinylidene difluoride) (PVDF) composites. The effect of PANI:PVDF composite on the performance of the solar cells was explored and the cells were characterized by current voltage (I−V) measurements under a solar simulator generating AM1.5 light (1000 W/m2) irradiance. It was found that solar cells containing ITO/PANI:PVDF photo-anode are likely to improve photocurrent and power conversion efficiency in a way superior to that containing only ITO as photo-anode. Furthermore, PANI:PVDF composite enhanced the hole extraction at photo-anode/photo-active layer interface via the high electrical conductivity of PANI and the ferroelectricity of PVDF.

Structural and microwave dielectric properties of ferroelectric poly(vinylidene difluoride)–polyaniline composite thin films

Nano composites of poly(vinylidene difluoride) (PVDF)–polyaniline (PANI) were prepared by spin coating method. Also, the influence of PANI doping (20, 30 and 40% by weight) on the microwave dielectric parameters was investigated. The structural aspects of samples were studied by atomic force microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Dielectric properties of PVDF:PANI composites were characterized as a function of composition and frequency. The microwave dielectric constant increased smoothly with an increase in the concentration of PANI. Moreover, when the PANI content reaches 40wt.%, there is a transition from an insulator to semiconductor.

Effect of Temperature on the Electrical and Gas Sensing Properties of Polyaniline and Multiwall Carbon Nanotube Doped Polyaniline Composite Thin Films

In the present work we have reported the effect of temperature on the gas sensing properties of pure Polyaniline (PANI) and Multiwall carbon nanotube (MWNT) doped PANI composite thin film based chemiresistor type gas sensors for hydrogen gas sensing application. PANI and MWNT doped PANI composite were synthesized by in situ chemical oxidative polymerization of aniline using ammonium persulfate in an acidic medium. The thin sensing film of chemically synthesized PANI and MWNT doped PANI composite were deposited onto finger type Cu-interdigited electrodes using spin cast technique to prepared chemiresistor type gas sensor. The electrical properties of these composite thin films were characterized by I-V measurements as function of temperature. The I-V measurement revealed that conductivity of composite thin films increased as the temperature increased. The changes in resistance of the composite thin film sensor were utilized for detection of hydrogen gas. It was observed that at room temperature, MWNT doped PANI composite sensor shows higher response value and sensitivity with good repeatability in comparison to pure PANI thin film sensor. It was also observed that both PANI and MWNT doped PANI composite thin film based sensors showed unstable behavior as the temperature increased. The surface morphology of these composite thin films has also been characterized by scanning electron microscopy (SEM) measurement.

Thin films of polyaniline–polyacrylic acid composite by chemical bath deposition

Polyaniline (PANI)–polyacrylic acid (PAA) composite thin films were deposited at room temperature on glass and polymethyl methacrylate substrates by introducing these into a freshly prepared chemical bath of HCl, PAA, aniline monomers and (NH 4) 2S 2O 8. Compared to the single PANI films, which were obtained from the same bath constitution but without PAA solution, the composite films showed a red shift at the maximum optical transmittance peak and a slightly lower electrical conductivity. Fourier transform infrared spectroscopy studies of the PANI composite thin films indicated the presence of the acid-base reaction product between PANI and PAA, as well as PAA molecule incorporation in the films. Atomic force microscopy analysis also showed morphologic and mechanical elasticity differences between the single PANI film the composite films deposited by the chemical bath method.