In this thesis, a series spirobifluorene derivatives were designed and synthesized, inwhich diarylethene moiety was functionalized for photochromic behavior and fullerenemoiety was functionalized for nonlinear optics and organic-inorganic hybrid photovoltaic cell,respectively. In sum, this thesis was divided into six chapters.In the introductory chapter1, we presented a comprehensive overview of the meolecularand electronic structure, synthetic pathways and application of spirobifluorene-basedcompounds.Notiveably, emphasis was placed on the synthetic pathways of precursors as wellas diverse target compounds, which threw a light on the new spirobifleorene-basedcompounds designed in this thesis.In chapter2, two novel spirobifluorene-diarylethenes compounds with respectivethiophene (11a) and furan (12a) as heterocyclic aryl groups were successfully synthesized andtheir photochromic properties were examined in hexane and acetonitrile, respectively. Theresults indicated that they showed good photochromic behaviors in both solutions. Particularly,the photochromic reaction rates of11a and12a in hexane were two and five times than thosein acetonitrile, respectively, and the conversion rates of them were1.44and1.36times thanthose in acetonitrile, respectively. In addition to photochromism, thermal stabilities andthermal irreversibility were studied. Specifically, thermal stabilities of11a,12a and13a(without spirobifluorene and with thiophen as heterocyclic aryl group) were recorded bythermogravimetry, and the results showed that the50%loss weight temperature of12a was21oC higher than that of11a, and94oC higher than that of13a. Thermal irreversibility ofring-closed forms11b,12b and13b were estimated by heating a toluene solution of them. Onthe basis of UV analysis,95%of12b and76%of11b were recovered unchanged afterheating, in contrast to only42%for13b. To sum up, the thermal stability and thermalirreversibility orders were2a>11a>13a and12b>11b>13b. These results showed that thermalstabilities of diarylethenes compounds were greatly improved due to spirobifluorene or furangroups in the molecules.In chapter3, six fullerene derivatives containing spirobifluorene (22and23) or triphenylimidazole (24-27) were synthesized and confirmed by IR,1H NMR,13C NMR,MALDI-TOF-MS. Their UV and fluorescence spectra were fully studied in this section.Result showed that new absorption bands were observed at432nm and703nm, and all offullerene derivatives showed similar fluorescent feature in which the maximum peaks locatedat about710nm with low quantum yields. Meanwhile, the solvent effects of these derivatives were studied, showing that all of these derivatives were not sensitive to the polarization ofsolvents. Addtionally, cyclic voltammetry results showed that the reductions of thesederivatives shifted10-480mv to negative values in comparison of C60, which indicatedenhanced electron-accepting abilities by functionalizing the [60]fullerene.In chapter4, the nonlinear optical properties of those six fullerene derivatives (22-27)were measured by Z-scan technique. Results indicated that all the derivatives of C60weresuperior to C60. The two photon absorption cross sections (TPCS) of22was12000GM,which was five times that of compound23with formaldehyde in spirobifluorene, and theoptical limiting threshold of22was8J/cm2less than23's. These results showed thatcompound22was a more excellent candidate for nonlinear optical materials than23. Inanother pair, compound24employed a much larger π-conjugated system than26did. As aresult, the TPCS of24was4times larger than26's and the optical limiting threshold of24was8.9J/cm2less than26's. So, in this section, we demonstrated a new method to enhancenonlinear optical properties by using [C60] fullerene as electron-acceptor and spirobifluoreneor triphenyl imidazole as electron-donors, and by inviting large π-conjugated system assubstituent.In chapter5, two novel fullerene [C70] derivatives (28and29) were synthesized and theirstructures were confirmed by FT-IR, MS,1H NMR and MALDI-TOF-MS. Comparing theirUV and electrochemical properties we found that both derivatives displayed similarabsorption profiles and reduction peak while the fluorescence intensity of28was higher thanthat of29by introduction of fluorophore aldehyde group in28. What is more, theirthird-order and five-order nonlinear optical properties were also researched by Z-scantechnique, showing that their third-order nonlinear refractive coefficients were2.98×10-14esuand2.82×10-14esu, respectively, which was about an order larger than those of the otherfullerene [C60] derivatives. At the same time,28and29displayed strong two-photon-inducedexcited state absorption (five-order nonlinear), and the excited state absorption cross sectionswere5.78×10-18cm-2 and4.26×10-18cm-2respectively, which proved themselvesprospective optical limiters.In chapter6, CdSe QDs were synthesized and characterized by SEM, XRD, UV-Vis andInfrared spectrum. Specifically, four kinds of Quantum Dot Sensitized Solar Cell (QDSSCs)were fabricated through electrophoretic deposition of four respective spirobifluorene-fullerenecompounds (22,23,28,29) and CdSe QDs on thin films of SnO2. The photovoltaic curves ofthose cells were measured at AM1.5. Results showed that the energy conversion efficienciesof those cells were uniformly greater than those of cells hybrided by corresponding fullerenes (C60 and C70). Among them, the energy conversion efficiency of those cells hybrided by23and29were23.8%and72.9%higher than those of C60and C70 respectively. At the same time,compound29with formaldehyde in spirobifluorene displayed60.7%energy conversionefficiency greater than28did, which could be explained by the hydrogen bond betweenformaldehyde and CdSe QDs stabilizer. Presumably a much better compatibility to CdSe QDsof spirobifluorene-fullerene compounds may be responsible for those results. |