Y.G. Gudage

Bio: Y.G. Gudage is an academic researcher from Dr. Babasaheb Ambedkar Marathwada University. The author has contributed to research in topics: Thin film & Band gap. The author has an hindex of 14, co-authored 19 publications receiving 887 citations.

Studies on tin oxide-intercalated polyaniline nanocomposite for ammonia gas sensing applications

Abstract: Thin films of tin oxide-intercalated polyaniline nanocomposite have been deposited at room temperature, through solution route technique. The as-grown films were studied for some of the useful physicochemical properties, making use of XRD, FTIR, SEM, etc. and optical methods. XRD studies showed peak broadening and the peak positions shift from standard values, indicating presence of tin oxide in nanoparticles form in the polyaniline (PANI) matrix. FTIR study shows presence of the Sn–O–Sn vibrational peak and characteristic vibrational peaks of PANI. Study of SEM micrograph revealed that the composite particles have irregular shape and size with micellar templates of PANI around them. AFM images show topographical features of the nanocomposite similar to SEM images but at higher resolution. Optical absorbance studies show shifting of the characteristics peaks for PANI, which may be due to presence of tin oxide in PANI matrix. On exposure to ammonia gas (100–500 ppm in air) at room temperature, it was found that the PANI film resistance increases, while that of the nanocomposite (PANI + SnO2) film decreases from the respective unexposed value. These changes on removal of ammonia gas are reversible in nature, and the composite films showed good sensitivity with relatively faster response/recovery time. © 2009 Elsevier B.V. All rights reserved.

Studies and correlation among the structural, optical and electrical parameters of spray-deposited tin oxide (SnO2) thin films with different substrate temperatures

Abstract: Thin films of tin oxide (SnO2) have been grown by using a simple and economical spray pyrolysis technique. The deposition temperature was optimized to 450 °C, while the concentration and quantity of the solution were kept fixed at 2 M and 20 ml, respectively. X-ray diffraction patterns (XRD) studies reveal that the material deposited is polycrystalline SnO2 having primitive tetragonal structure. The lattice parameters, grain size, microstrain and dislocation densities were calculated and correlated with the substrate temperature. The transmission spectra showed a sharp decrease in transmission at the absorption edge and a good form of interference pattern. The figure of merit has been calculated from transmission spectra. Low sheet resistance ∼16.03 Ω/sq cm and high visible transmission (∼86%) were obtained when the films were deposited at the substrate temperature of 450 °C. From electrical measurements, the resistivity was found to be 11.5×10−4 Ω cm, while the carrier concentration was calculated to be 8.81×1021 cm−3.

Semiconductor metal oxide gas sensors: A review

Abstract: This review paper encompasses a detailed study of semiconductor metal oxide (SMO) gas sensors. It provides for a detailed comparison of SMO gas sensors with other gas sensors, especially for ammonia gas sensing. Different parameters which affect the performance (sensitivity, selectivity and stability) of SMO gas sensors are discussed here under. This paper also gives an insight about the dopant or impurity induced variations in the SMO materials used for gas sensing. It is concluded that dopants enhance the properties of SMOs for gas sensing applications by changing their microstructure and morphology, activation energy, electronic structure or band gap of the metal oxides. In some cases, dopants create defects in SMOs by generating oxygen vacancy or by forming solid solutions. These defects enhance the gas sensing properties. Different nanostructures (nanowires, nanotubes, heterojunctions), other than nanopowders have also been studied in this review. At the end, examples of SMOs are given to illustrate the potential use of different SMO materials for gas sensing.

Nanostructured Materials for Room-Temperature Gas Sensors

Abstract: Sensor technology has an important effect on many aspects in our society, and has gained much progress, propelled by the development of nanoscience and nanotechnology. Current research efforts are directed toward developing high-performance gas sensors with low operating temperature at low fabrication costs. A gas sensor working at room temperature is very appealing as it provides very low power consumption and does not require a heater for high-temperature operation, and hence simplifies the fabrication of sensor devices and reduces the operating cost. Nanostructured materials are at the core of the development of any room-temperature sensing platform. The most important advances with regard to fundamental research, sensing mechanisms, and application of nanostructured materials for room-temperature conductometric sensor devices are reviewed here. Particular emphasis is given to the relation between the nanostructure and sensor properties in an attempt to address structure-property correlations. Finally, some future research perspectives and new challenges that the field of room-temperature sensors will have to address are also discussed.

Nuclear Tracks in Solids (Principles and Applications)

Abstract: (1976). Nuclear Tracks in Solids (Principles and Applications) Nuclear Technology: Vol. 30, No. 1, pp. 91-92.