The optical properties of polypyrrole （Ppy） thin films upon 2 MeV electron beam irradiation changes with different doses. The induced changes in the optical properties for Ppy thin films were studied in the visible ...The optical properties of polypyrrole （Ppy） thin films upon 2 MeV electron beam irradiation changes with different doses. The induced changes in the optical properties for Ppy thin films were studied in the visible range 300 to 800 nm at room temperature. The optical band gap of the pristine Ppy was found to be 2.19 cV and it decreases up to 1.97 eV for a 50 kGy dose of 2 MeV electron beam. The refractive index dispersion of the samples obeys the single oscillator model. The obtained results suggest that electron beam irradiation changes the optical parameters of Ppy thin films.展开更多
Copper telluride onion flower like microstructures, constructed by quantum dots with various diameters, were obtained by a potentiostatic electrodeposition method at room temperature. The structural, optical, surface ...Copper telluride onion flower like microstructures, constructed by quantum dots with various diameters, were obtained by a potentiostatic electrodeposition method at room temperature. The structural, optical, surface morphology, compositional analysis and Raman spectra properties of the deposited films have been studied using X-ray diffraction, optical absorption with scanning electron microscopy, EDAX, and Raman spectroscopy, The electrolyte concentration and deposition time can be used to control the diameter of the electrodeposited quantum dots to within a range of 50-55 nm. The films are found to be stoichiometric in composition. The optical constants such as the optical band gap energy and the optical absorption spectra show significant variation in their values with a change in deposition time. Upon deposition time the band gap energy increased from a value of 2.74 to 2.89 eV.展开更多
Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 V versus saturated calomel electrode （SCE） by using the electrochemical polym...Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 V versus saturated calomel electrode （SCE） by using the electrochemical polymerization method. The PPy thin films were deposited at room temperature at various monomer concentrations ranging from 0.1 M to 0.3 M pyrrole. The structural and optical properties of the polypyrrole thin films were investigated using an X-ray diffractometer （XRD）, FTIR spectroscopy, scanning electron microscopy （SEM）, and ultravioletvisible （UV-vis） spectroscopy. The XRD results show that polypyrrole thin films have a semi crystalline structure. Higher monomer concentration results in a slight increase of crystallinity. The polypyrrole thin films deposited at higher monomer concentration exhibit high visible absorbance. The refractive indexes of the polypyrrole thin films are found to be in the range of 1 to 1.3 and vary with monomer concentration as well as wavelength. The extinction coefficient decreases slightly with monomer concentration. The electrochemically synthesized polypyrrole thin film shows optical band gap energy of 2.14 eV.展开更多
基金the Department of Science and Technology, New Delhi, for financial support under the DST-PURS Eschemeat Shivaji University,Kolhapur
文摘The optical properties of polypyrrole （Ppy） thin films upon 2 MeV electron beam irradiation changes with different doses. The induced changes in the optical properties for Ppy thin films were studied in the visible range 300 to 800 nm at room temperature. The optical band gap of the pristine Ppy was found to be 2.19 cV and it decreases up to 1.97 eV for a 50 kGy dose of 2 MeV electron beam. The refractive index dispersion of the samples obeys the single oscillator model. The obtained results suggest that electron beam irradiation changes the optical parameters of Ppy thin films.
文摘Copper telluride onion flower like microstructures, constructed by quantum dots with various diameters, were obtained by a potentiostatic electrodeposition method at room temperature. The structural, optical, surface morphology, compositional analysis and Raman spectra properties of the deposited films have been studied using X-ray diffraction, optical absorption with scanning electron microscopy, EDAX, and Raman spectroscopy, The electrolyte concentration and deposition time can be used to control the diameter of the electrodeposited quantum dots to within a range of 50-55 nm. The films are found to be stoichiometric in composition. The optical constants such as the optical band gap energy and the optical absorption spectra show significant variation in their values with a change in deposition time. Upon deposition time the band gap energy increased from a value of 2.74 to 2.89 eV.
基金financial support under the DST-PURSE scheme at Shivaji University,Kolhapur
文摘Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 V versus saturated calomel electrode （SCE） by using the electrochemical polymerization method. The PPy thin films were deposited at room temperature at various monomer concentrations ranging from 0.1 M to 0.3 M pyrrole. The structural and optical properties of the polypyrrole thin films were investigated using an X-ray diffractometer （XRD）, FTIR spectroscopy, scanning electron microscopy （SEM）, and ultravioletvisible （UV-vis） spectroscopy. The XRD results show that polypyrrole thin films have a semi crystalline structure. Higher monomer concentration results in a slight increase of crystallinity. The polypyrrole thin films deposited at higher monomer concentration exhibit high visible absorbance. The refractive indexes of the polypyrrole thin films are found to be in the range of 1 to 1.3 and vary with monomer concentration as well as wavelength. The extinction coefficient decreases slightly with monomer concentration. The electrochemically synthesized polypyrrole thin film shows optical band gap energy of 2.14 eV.
