Deepak S. Upadhye

Study of room temperature LPG sensing behavior of polyaniline thin film synthesized by cost effective oxidative polymerization technique

Polyaniline thin films doped with an inorganic acid were deposited on glass substrate using simple and cost effective oxidative polymerization technique. As-synthesized thin film of polyaniline was studied with different characterization techniques. The formation of polyaniline on glass substrate was confirmed by X-ray diffraction and UV spectroscopy. Surface morphological investigation was performed using scanning electron microscopy. Gas sensing behavior of polyaniline thin film was studied by I–V measurements before and after liquefied petroleum gas (LPG) exposure at room temperature, based on change in electrical resistance. The observed result shows polyaniline thin film sensor is efficient for LPG detection at room temperature.

An economic approach to fabricate photo sensor based on nanostructured ZnO thin films

Nanostructural ZnO Thin Films have been synthesized by simple and economic Chemical Bath Deposition technique onto glass substrate with bath temperature at 60°C for 1 hour. Structural, Optical, Electrical and topographical properties of the prepared Thin Films were investigated by GIXRD, I-V Measurement System, UV-Visible Spectrophotometer and AFM respectively. Calculated lattice parameters are in good agreement with the standard JCPDS card (36-1451) values, exhibits Hexagonal Wurtzite crystal structure. I-V Measurement curve has shown ohmic nature in dark condition and responds to light illumination which reveals Photo sensor properties. After illumination of 60W light, decrease in resistance was observed from 110.9 KΩ to 104.4 KΩ. The change in current and calculated Photo sensitivity was found to be 3.51 µA and 6.3% respectively. Optical band gap was found to be 3.24 eV. AFM images revealed uniform deposition over entire glass substrate with 32.27 nm average roughness of the film.

Annealing effect on Cu2S thin films prepared by chemical bath deposition

In present work Cu2S thin film fabricated on glass substrate by simple, cost effective chemical bath deposition method subsequently it annealed at 150°c.These films were studied for their structural, optical and electrical properties using X-ray diffraction, UV-vis spectrophotometer and I-V system. The results show successful synthesis of Cu2S thin films and improvement in crystalline nature of the thin film which resulted in reduced bad gap and resistance of the film. Thus these thinfilms prove to be a promising candidate for solar cell application.

Economic approach for fabricating nontoxic Cu2ZnSnS4 (CZTS) thin films for solar cell applications

In the present work, Cu2ZnSnS4 (CZTS) thin films have been fabricated onto the glass substrate by simple and economic chemical bath deposition technique, using optimized temperature of 50°C and deposition time of 60 min, which is significantly lower than earlier reports. The CZTS thin films were characterized for morphological, compositional, optical and electrical properties using scanning electron microscopy, energy dispersive X-ray analysis, UV-vis spectrophotometer and I-V system for photosensitivity.

LPG ammonia and nitrogen dioxide gas sensing properties of nanostructured polypyrrole thin film

Nanostructured Polypyrrole thin film was synthesized by easy and economic chemical oxidative polymerization technique on glass at room temperature. The prepared thin film of Polypyrrole was characterized by optical absorbance study by UV-visible spectroscopy and electrical study by I-V measurement system. The optical absorbance spectrum of Polypyrrole shows two fundamental peaks in region of 420 and 890 nm, which confirms the formation of Polypyrrole on glass substrate. The I-V graph of nanostructured Polypyrrole represents the Ohmic nature. Furthermore, the thin film of Polypyrrole was investigated by Scanning electron microscopy for surface morphology study. The SEM micrograph represents spherical nanostructured morphology of Polypyrrole on glass substrate. In order to investigate gas sensing properties, 100 ppm of LPG, Ammonia and Nitrogen Dioxide were injected in the gas chamber and magnitude of resistance has been recorded as a function of time in second. It was observed that nanostructured Polypyrro...

Effect of HCl doping on optoelectrical and LPG sensing properties of nanostructured polyaniline thin films

Nanostructure Polyaniline thin films doped with 0.5 M, 0.7 M, and 1 M of HCL were synthesized by simple and inexpensive chemical oxidative polymerization technique at room temperature. All prepared thin films of Polyaniline were characterized by optical absorbance study by UV-visible spectroscopy. The absorbance spectrum of Polyaniline shows three fundamental peaks at 356, 419 and 820 nm with increase in absorption intensity. The electrical study shows magnitude of resistance of HCL doped Polyaniline is dependent on doping level. Furthermore, the thin film of Polyaniline was investigated by Scanning electron microscopy for surface morphology study. The SEM micrograph represents irregular granular morphology. In order to investigate LPG sensing properties, I-V characteristics of the Polyaniline films doped with 0.5 M, 0.7 M, and 1 M of HCL were recorded at room temperature in presence of air and 100 ppm of LPG. The observed values of sensitivity found to be 7.21%, 9.85% and 17.46 % for 0.5 M, 0.75 M, and 1...

Wet chemically grown composite thin film for room temperature LPG sensor

We have synthesized thin film of zinc oxide-polyaniline (ZnO/PANI) composite using a simple wet chemical approach. As-synthesized ZnO/PANI composite thin film studied using different characterization techniques. The optical study reveals the penetration and interaction of PANI molecules with ZnO thin film. Prominent blue shift in UV-vis due to interaction between ZnO and PANI indicate presence of zinc oxide in polyaniline matrix. It is observed that ZnO thin film is not sensitive to LPG (liquefied petroleum gas) at room temperature. On the other hand ZnO/PANI composite thin film shows good response and recovery behaviors at room temperature.

Mn doped nanostucture ZnO thin film for photo sensor and gas sensor application

Mn doped nanostructure ZnO thin film prepared by soft chemically route method. ZnO thin films were deposited on glass substrate by successive ionic layer adsorption and reaction technique (SILAR). After deposit ZnO thin film dipped in MnSO4 solution for 1 min. The optical properties as absorbance were determined using UV-Spectrophotometer and band gap was also calculated. The Structural properties were studied by XRD. The improvement in gas sensing properties was found to enhance after doping of Mn on ZnO thin film. The Photo Sensor nature was calculated by I-V characteristics.

Growth of nanocrystalline Zn0.75Mg0.25S thin film by solution growth technique and their characterization as a window layer for solar cell

ABSTRACT Zn0.75Mg0.25S thin film was grown by solution growth technique. The as-grown thin film was examined to study its structural and optoelectronic properties. The formation of pure ZnMgS/O phase with wurtzite structure was confirmed by XRD. Optical bandgap (∼3.69 eV) was estimated through Taucs plot obtained from UV-Vis spectroscopic data analysis. The existence of ZnMgS/O phonons was confirmed from the peaks obtained in Raman spectra. The PL spectrum shows band edge near UV emission. Decrease in resistance after light illumination was observed in I-V characteristics results in 98% photosensitivity.

Room temperature gas sensing properties of polypyrrole-gold nanocomposite thin film

ABSTRACT Thin films of polypyrrole and polypyrrole-gold nanocomposite were deposited on the still substrate by an electrochemical deposition technique. Electrical resistivity of both thin films were investigated which shows the ohmic nature with a decrease in resistivity in the polypyrrole-gold nanocomposite. Surface morphology of both samples represents the nanofiber like morphology randomly oriented on the still substrate whereas the presence of gold nanoparticles in polymer matrix was confirmed by EDAX spectrum. The room temperature gas sensing was studied in presence of 50 ppm of ammonia gas and enhancement in sensitivity was observed in the case of polypyrrole-gold nanocomposite.