02182nas a2200205   4500008004100000022001400041245016400055210006900219260011000288300001600398490000700414520129900421100002101720700002401741700002401765700002301789700001701812700002601829856012101855       2014                        eng d  a1477-922600aNew Ru(II)/Os(II)-polypyridyl complexes for coupling to TiO2 surfaces through acetylacetone functionality and studies on interfacial electron-transfer dynamics0 aNew RuIIOsIIpolypyridyl complexes for coupling to TiO2 surfaces   aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcSEP  a13601-136110 v433 a<p>New Ru(II)- and Os(II)-polypyridyl complexes have been synthesized with pendant acetylacetone (acac) functionality for anchoring on nanoparticulate TiO2 surfaces with a goal of developing an alternate sensitizer that could be utilized for designing an efficient dye-sensitized solar cell (DSSC). Time-resolved transient absorption spectroscopic studies in the femtosecond time domain have been carried out. The charge recombination rates are observed to be very slow, compared with those for strongly coupled dye molecules having catechol as the anchoring functionality. The results of such studies reveal that electron-injection rates from the metal complex-based LUMO to the conduction band of TiO2 are faster than one would expect for an analogous complex in which the chromophoric core and the anchoring moiety are separated with multiple saturated C-C linkages. Such an observation is rationalized based on computational studies, and a relatively smaller spatial distance between the dye LUMO and the TiO2 surface accounted for this. Results of this study are compared with those for analogous complexes having a gem-dicarboxy group as the anchoring functionality for covalent binding to the TiO2 surface to compare the role of binding functionalities on electron-transfer dynamics.</p>1 aBanerjee, Tanmay1 aBiswas, Abul, Kalam1 aSahu, Tuhin, Subhra1 aGanguly, Bishwajit1 aDas, Amitava1 aGhosh, Hirendra, Nath  uhttps://library.ncl.res.in/content/new-ruiiosii-polypyridyl-complexes-coupling-tio2-surfaces-through-acetylacetone-002116nas a2200217   4500008004100000022001400041245019300055210006900248260007100317300001400388490000800402520119800410100002101608700002401629700002301653700002401676700001701700700002301717700002601740856013201766       2014                        eng d  a1932-744700aSuperior grafting and state-of-the-art interfacial electron transfer rates for newly designed geminal dicarboxylate bound ruthenium(II)- and osmium(II)-polypyridyl dyes on TiO2 nanosurface0 aSuperior grafting and stateoftheart interfacial electron transfe  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB  a3864-38770 v1183 a<p>Two new Ru(II)-/Os(II)-polypyridyl based sensitizer dyes with geminal dicarboxylic acid group as the binding unit for superior grafting of the dye to TiO2 have been designed and synthesized. Steady-state photochemical studies of the two sensitizer dyes in presence of TiO2 in water confirm strong binding of the dyes to TiO2. Femtosecond transient absorption studies of these newly synthesized dyes on TiO2 nanosurface have been carried out in water and the results have been compared with those for the corresponding 4,4'-dicarboxy-2,2'-bipyridine analogues of the dyes. While the charge recombination rates are considerably slower, interestingly, the electron injection rates are very fast for multiple saturated C-C linkages present between the chromophoric core and the anchoring moiety. The origin and the consequences of such profound effects on the ultrafast interfacial dynamics are discussed. This is the first report on the ultrafast transient absorption studies of dyes with geminal dicarboxylic acid binding groups, which we believe will add significantly to the present research efforts toward the development of robust and efficient dyes for use in dye solar applications.</p>1 aBanerjee, Tanmay1 aBiswas, Abul, Kalam1 aReddy, Upendar, G.1 aSahu, Tuhin, Subhra1 aDas, Amitava1 aGanguly, Bishwajit1 aGhosh, Hirendra, Nath  uhttps://library.ncl.res.in/content/superior-grafting-and-state-art-interfacial-electron-transfer-rates-newly-designed-geminal-0