Polymer blend electrolyte membrane was prepared for dye sensitized solar cells based on poly ethylene oxide and polyvinylidene fluoride-co-hexaflouropropylene (PVDF-HFP) filled with surface modified Titanium dioxide (M-TiO 2 ) nanofillers. The surface of TiO 2 was modified using Aminopropyltrimethoxysilane. The electrochemical studies indicated that the addition of surface modified nanoparticles increase the ionic conductivity up to 7.21x 10 -4 S/cm for 7 wt%, whereas the ionic conductivity about 8.14×10 -5 S/cm with the addition of unmodified counterpart as the filler into the PEO/PVDF-HFP blend system. In addition to this ionic mobility, charge carrier concentration, ion diffusion coefficient also found to increase with the addition of surface modified TiO 2 nanoparticles. Wide angle X-ray diffraction (WAXD) results showed the change in the crystalline phase of PEO/PVDF-HFP blend electrolyte with the addition of M-TiO 2 . The influence of the TiO 2 nanoparticles surface functionality on the degree of crystallinity of the polymer matrix was analyzed using differential scanning Calorimetry (DSC). Thermo mechanical behavior of the composite membranes was studied by dynamical mechanical Analysis (DMA). The thermo gravimetric investigations (TGA) of membranes indicated the thermal degradation temperatures of hybrid nanocomposites were enhanced upon the addition of nanosized inorganic fillers. The morphological characterizations were carried out by atomic force microscopy (AFM). The solid state dye sensitized solar cell has been fabricated by using silane modified TiO 2 /PEO/PVDF-HFP polymer nanocomposites electrolyte, multiwalled carbon nanotube (MWCNT)/Nafion ® as counter electrode. The photovoltaic characteristics of constructed cells showed an enhancement of open circuit voltage (V oc ) from 0.62 to 0.71 V andthe best efficiency achieved about 2.84%. The enhancement of DSSC was further confirmed by electrochemical impedance spectra (EIS) spectra studies for lowest Warburg resistance (R diff ).

Stoichiometric hydroxyapatite with Ca/P molar ratio, 1⋅ ⋅67, was synthesized using hen's eggshell as calcium source and phosphoric acid by precipitation method. Conventional EDTA titration and gravimetric methods were adopted to estimate the amount of calcium and phosphorous, respectively. Fourier-transform infrared (FT-IR) and X-ray diffraction (XRD) techniques were employed to investigate the formation of the HAP phase. Thermal analysis (TG-DTA) was carried out to investigate the thermal stability of HAP powder. FT-IR spectra show the characteristic peaks for phosphate and hydroxyl groups. XRD results reveal that the major characteristic peaks of HAP appear in the region of approximately 26°, 28°, 29°, 30-35°, 39°, 46°, 49° and 50° (2θ θ) and also indicate that there are no occurrences of secondary phases during HAP formation. TG-DTA result depicts that the synthesized HAP was stable up to 1300°C.

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Metallic materials having good mechanical properties, high corrosion resistance, and good compatibility with biological materials are used as orthopedic devices. Type 316L stainless steel is the most widely used material for implant fabrication in India for orthopedic applications owing to their good corrosion resistance, hot and cold workability, excellent mechanical properties, and availability at low cost. However, it faces corrosion-related problems in physiological environment and thus releases toxic metal ions into the tissues surrounding the implants. Hence, hydroxyapatite (HAP) coatings over the metal implant have been developed as an alternative method to improve the surface conditions of the base metal. In the present investigation, the development of a sol-gel-derived hydroxyapatite coating on 316L SS is being explored. The corrosion resistance behavior of the coating was assessed through electrochemical studies involving cyclic polarization experiments and impedance analysis in Ringer's solution. The results have indicated that the sol-gel-derived HAP coatings exhibited excellent resistance to localized attack on pristine 316L SS.