| Phthalocyanines and porphyrins owing to the high thermal and chemical stabilities,as well as the unique optical,electrical,and properties,have been expected to be widely applied application in materials science,such as molecular electronics,molecular information storage,nonlinear optics,and material science etc.Introducing various substitutes on the periphery of the phthalocyanine and/or porphyrin macrocycle?s?,the solubility of the resulting compounds enhanced and the energy-levels of the front molecular orbits can be easily tuned.Furthermore,through coordinating four isoindole or pyrrole nitrogen atoms,sandwich-type phthalocyaninato and/or porphyrinato rare earth complexes are fabricated.Due to inherent air-stable ambipolar performance and excellent electrocatalytic activity,they have been used as the excellent building blocks for the design and synthesis of novel electrical active materials with application potentials in field effect transistors and chemical recognition.In this thesis,several sandwich-type phthalocyaninato and/or porphyrinato rare earth complexes are designed and synthesized.Then these sandwich-type molecules are self-assembled into nano/microstructures with different morphology depending on various intermolecular interactions.The relationship between molecular structures,nano/microstructures and the semiconduting performance of the complexes has been established.The main contents of this thesis include the following points:1.Controlled morphology of self-assembled microstructures via solvent-vapor annealing temperature and ambipolar OFET performance based on a tris?phthalocyaninato?europium derivativeAnovelhomolepticsandwich-type tris[2,3,9,10,16,17,23,24-octa?naphthoxy?phthalocyaninato]europium triple-decker complex Eu2[Pc?ONh?8]3?1?,having a low-lying LUMO energy level of–4.0 eV and relatively narrow HOMO–LUMO separation of 1.13 eV,was designed and successfully synthesized.The OFET devices fabricated from this compound using a solution-based quasi-Langmuir-Sh?fer?QLS?method display air-stable ambipolar performance with the carrier mobilities of?2.5±0.5?×10-6 cm2·V-1·s-1 for holes and?2.3±0.3?×10-6 cm2·V-1·s-1 for electrons,indicating its ambipolar semiconducting nature.Upon the o-dichlorobenzene?DCB?solvent vapor annealing at the temperature of 60,80,100,and 120?,a fine combination of the“oriented attachment”with Ostwald ripening process under controlled SVA environments leads to the growth of the first two-dimensional?2D?micro-sheet microstructures with tunable morphology including the fragment-like irregular polygons,quasi-four-corner sheets,squares,and clovers,respectively,from the nanoparticles of the pristine QLS film.This in turn results in the tunable OFET device performance with the carrier mobilities changing as a result of the morphologies and crystallinities.The best result was achieved for the most crystalline 2D squares-based devices with the carrier mobilities of 0.11±0.03 cm2·V-1·s-1 for holes and 0.06±0.02 cm2·V-1·s-1 for electrons.2.Unprecedented Reduced Graphene Oxide-Involved Bilayer Heterojuntion Organic Field Effect Transistors with Exceptional Excellent PerformanceFor the purpose of fabricating next generation of microelectronics and photonics,the transistor that simultaneously provides high-efficiency charge transport and air-stable ambipolar performance becomes highly desired.In this paper,the reduced graphene oxide?rGO?with good conductivity has been fabricated into bilayer heterojunction field-effect transistors 1/rGO?HFET-1?and 2/rGO?HFET-2?for the first time,with sandwich mixed?phthalocyaninato??porphyrinato?europium triple-deckers?Pc'?Eu?Pc'?Eu[TP?OH?PP]{Pc'=Pc,[Pc?OPh?8]}?1,2?possessing an intrinsic air-stable ambipolar semiconducting nature,using a simple two-step solution-processing approach.The resulting bilayer heterojunction devices exhibit significantly improved air-stable ambipolar performance with the carrier mobilities of about 107108 fold higher than those of pristine triple-deckers.In particular,due to the heterojunction effect in an“accumulation mode”,the device HFET-2 shows the ultrahigh and balanced mobilities between hole,30.9 cm2·V-1·s-1,and electron,39.6cm2·V-1·s-1,with the optimized ON/OFF ratio of 103 for both carriers,representing the best result for ambipolar OFET devices reported thus far.3.High sensitive ambipolar response towards oxidizing NO2 and reducing NH3based on bis?phthalocyaninato?europium semiconductorsHigh sensitive chemical sensors towards NO2 and NH3 based on the self-assembled nanostructures of the heteroleptic and homoleptic bis?phthalocyaninato?europium complexes with octanaphthoxy phthalocyaninato ligands named Eu?Pc?[Pc?ONh?8]?1?and Eu[Pc?ONh?8]2?2?have been developed.The good conductivity,high crystallinity and large specific surface area for the self-assemblies of 1 renders it excellent sensing property for either electron-accepting gas NO2 in 50–250 ppb range or electron-donating gas NH3 in 2.5–12.5 ppm range due to the optimized molecular packing in the uniform-sized nanoparticles depending on the effective intermolecular interaction between double-decker molecules,among the best results of phthalocyanine-based chemical sensors for detection of NO2 and NH3 at room temperature.Interestingly,self-assemblies of 1 exhibited n-type response to NO2 and p-type response to NH3,which is the first example of ambipolar charge-transporting gas sensors fabricated from single-component organic semiconductors.However,the self-assemblies of 2 with sixteen bulky naphthoxy groups at the periphery of two Pc rings only present an n-type response to strong oxidant gas NO2 in a relative high concentration of0.5–1.5 ppm,while are insensitive to weak reducing gas NH3 due to the existence of great steric hindrance from bulky naphthoxy groups and more traps and/or defects in self-assemblies.4.A covalently joined porphyrin-pillararene derivative for chemical sensing of dihydroxybenzene isomersA novle porphyrin-pillararene derivative H2[T?C?C-P5?PP]possessing good molecular recognition ability and good conductivity depending on the?-conjugate electron structure of the porphyrin is designed and synthesized.After Introduced the pillarene onto the porphyrin periphery,the self-assembly of porphyrin-pillararene derivative H2[T?C?C-P5?PP]formed1D rod-like morphology with high crystallinity.The electronchemical sensor based on this self-assembly exhibits highly selectivity performance toward dihydroxybenzene isomers depending on the host-guest recognition effect of pillarene. |
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