Performance Parameters of Graphite and Platinum Counterelectrode Based Dye Sensitized Solar Cells

In the present course of work, we have successfully prepared a dye sensitized solar cell  (DSSC) based on TiO2 film coated ITO (indium doped tin oxide) glass photo anode, N719 dye as sensitizer, iodine as redox couple electrolytes and a counter electrode with graphite film coated ITO glass. Powder of TiO2 was synthesized by sol gel route technique. The XRD pattern confirms the anatase and rutile phase of TiO2. Crystallite size of TiO2 powder is 75.5nm. The TiO2 paste was coated on ITO by doctor blade technique. The FTIR spectrum shows a main peak corresponding to 495cm-1. However, UV-Visible absorbance of graphite/ITO glass and platinum/ITO glass were obtained as 20-25% and 7-17% respectively in the wavelength range of 300-800nm. The open circuit voltage of DSSC has been observed to be maximum 690.1mV and 619.5mV for platinum and graphite counter electrode respectively. The OCV decay shows the non linear nature. The fill factor values were obtained as 0.60 and 0.50 for platinum and graphite based electrode of DSSCs respectively. The efficiencies of DSSC with platinum/ITO and graphite/ITO electrodes were found to be 1.63% and 0.89% respectively.

Investigations on key aspects of solution growth L-Alanine strontium chloride trihydrate single crystal for non-linear optical and photonic applications

In the modern era materials with high NLO efficiency, better mechanical and thermal properties are on leading edge and highly demanded for their efficient use in optical communication and fibers optics. In the present course of work, authors have grown successfully single crystals of L-alanine strontium chloride trihydrate(LASRT) by slow evaporation solution and slow cooling techniques so as to meet the demand of industries. Structure of the grown crystal with lattice parameters were confirmed by employing powder XRD technique. Mechanical strain present in the lattice is determined as -7.066 x 10(-2) by Williamson-Hall relation. The newly grown crystals were subjected to HRXRD to assess crystal perfection and various types of defects. In this research, quality of the grown crystals is found moderately good. The specimen has better transmission nearly 44% as indicated by UV-Vis spectra. Various remarkable parameters like optical band gap, reflectance, refractive index, extinction coefficient and electrical susceptibility are determined. Some important electronic parameters are calculated by using Claussius-Mossottee relation. Thermal properties were also investigated in detail by subjecting the crystals to TGA/DTA measurements. By photo acoustic analysis, thermal diffusivity (alpha) is found 1.8816 x 10(-6) m(2)/s which indicates large heat bearable capacity of the grown sample. Mechanical stability of LASRT is determined larger than already reported LOMHCl and LLHBr single crystals by Nano-indentation technique. Results for nonlinear optical testing, crystalline perfection and optoelectronic parameters indicate its suitability for laser applications