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We are presenting our results based on unsymmetrical zinc phthalocyanine by adopting ‘push-pull’ concept for the nanocrystalline dye-sensitized solar cells. Using this sensitizer in combination with nonvolatile organic-solvent-based electrolytes, we obtained a photovoltaic efficiency of 1.52% under standard global AM 1.5 sunlight and compared the results with volatile organic-solvent based electrolyte. These devices exhibit admirable stability when subjected to continuous thermal stress at 60 oC for 1000 h. The sensitizer is thermally stable up to 150 oC and can be useful for roof top applications.

A series of plastic fats containing no transFA and having varying melting or plastic ranges, suitable for use in bakery, margarines, and for cooking purposes as vanaspati, were prepared from palm oil. The process of fractionating palm oil under different conditions by dry and solvent fractionation processes produced stearins of different yields. Melting characteristics of stearin fractions varied depending on the yield and the process. The lower-yield stearins were harder and had a wider plastic range than those of higher yields. The fractions with yields of about 35% had melting profiles similar to those of commercial vanaspati. The plastic range of palm stearins was further improved by blending them with corresponding oleins and with other vegetable oils. The plasticity or solid fat content varied depending on the proportion of stearin. Blends with higher proportions of stearins were harder than those with lower proportions. the melting profiles of some blends, especially those containing 40–60% stearin of about 25% yield and 40–60% corresponding oleins or mahua or rice bran oils, were similar to those of commercial vanaspati and bakery shortenings. These formulations did not contain any transFA, unlike those of commercial hydrogenated fats. Thus, by fractionation and blending, plastic fats with no transacids could be prepared for different purposes to replace hydrogenated fats, and palm oil could be utilized to the maximum extent.

A new high molar extinction coefficient ruthenium(II) bipyridyl complex 'cis-Ru(L1)(2,2'-bipyridine-4,4'-dicarboxylic acid) (NCS)2, BDF', where L1=4,4-bis(9,9-dibutyl-9H-fluorene-2-yl)-[2,2] bipyridine, has been synthesized and characterized by Fourier transform infrared (FTIR), hydrogen nuclear magnetic resonance (1H-NMR) and electrospray ionization mass (ESI-MASS) spectroscopes. The dye, upon anchoring onto mesoporous nano-crystalline TiO2solar cells, exhibited a broader photocurrent action spectrum, with a solar-to-electric energy conversion efficiency (?) of 6.58% (JSC=14.66?mA?cm?2, VOC=640?mV, fill factor=0.71) under sunlight at air mass (AM) 1.5, larger than the reference Z907 sensitized solar cell fabricated under similar conditions, which exhibited an ?-value of 4.65% (JSC=11.52?mA?cm?2, VOC=566?mV, fill factor=0.72). Absorption measurements and time-dependent density functional theory (TDDFT) calculations show that the increased conjugation length by introducing 9,9-dibutyl-9H-fluorene moiety relatively enhances the spectral response of the ancillary ligand and the corresponding BDF complex. The calculated dipole moments for BDF and Z907 are 17.71 and 16.34 Debye, respectively. The first three highest occupied molecular orbitals (HOMOs) of BDF have a t2gcharacter, as observed in Z907, while HOMO-4 and HOMO-5 have considerable sizable mixing from Ru-NCS with ?-orbitals of L1.