Papers by Keyword: C₆₀

Abstract: Electrical conductance of Si(111)6×6-Tl and Si(111)β√3×√3-Bi surfaces has been monitored in the course of fullerenes deposition. It has been found that dependence of surface conductivity on the adsorbed C60 dose can be understood in terms of charge transfer induced by interaction of fullerene molecules and substrate which can be explained by the acceptor-like behavior of fullerenes. For the Si(111)6×6-Tl surface decreasing of conductance is connected with depletion of metallic bands of the Tl double layer. For the Si(111)β√3×√3-Bi surface the conductivity is almost unchanged with C60 dose, but due to the fact that C60 layer on this surface form close-packed hexagonal arrays in the layer-by-layer mode, it can be used as a template for alkali-induced ultra-thin fulleride formation.

Abstract: Due to its excellent physical properties and inert chemical reaction activity of C₆₀, it is possible to synthesize solution-processing polymer containing C₆₀ utilizing the inclusive characteristics of polymer chain segment, and then to prepare organic/inorganic nanocomposites with enhanced some key properties. In order to harvest the visible light of TiO₂ effectively the surface modification of TiO₂ nanotube with polymer containing C₆₀ was carried out in this study. A series of characterizations were performed by SEM (scanning electron microscopy), TEM (transmission electron microscopy), Fourier-Transform Infrared (FTIR) spectra, UV-Vis (Ultra-violet visible spectroscopy), XRD patterns analysis. The results showed that the UV-Vis of resulting nanocomposite was almost covered the whole region of visible light. The photoconductivity response to visible light with low-power were studied based on interdigital electrodes of Au on flexible PET (polyethylene terephthalate) film substrate with casting method. The results indicated that the photoresponses of two kinds of polymer containing C₆₀ to weak visible light emerged photo-switching behavior, its recoverability was also rapidly, and the photoresponse of TiO₂ nanotube modified with two kinds of polymer containing C₆₀ to weak visible light also changed greatly. This illustrated that the organic-inorganic nanocomposites showed good activities to weak visible light. Photocatalytic efficiency was examined by selecting typical organic pollutants, some good results were obtained. It may develop organic-inorganic nanocomposites with external stimuli response, photocatalyst, et al.

Abstract: Organic layers deposited on various polarity substrates and the electronic structures of (PTCDA/TiOPc) on hydrophobic and hydrophilic substrates have been studied by ultraviolet photoemission spectroscopy. The difference between work function and polarity of the substrates induce the formation of an interface dipole with corresponding shift in the relative position of molecular levels across the interface. While the vacuum level and open circuit voltage show vastly difference respectively, the barrier between anode-organic or organic-cathode also changes from 0.75eV to 1.13eV or 0.35eV to 0.65eV. The results show the possibility of tuning the electronic structure by the modification of substrate and potential applications on performance enhancement in organic electronic devices.

Abstract: The covalent incorporation of C60 into one block of a poly(1,4-(2,5-dioctyloxy)phenylene vinylene)-based diblock copolymer resulted in a donor–acceptor diblock copolymer, which demonstrated a very efficient electron transfer upon excitation of the PPV block. The strong quenching of the photoluminescence from the PPV block indicated an efficient electron transfer at the donor–acceptor interface.

Abstract: The (C₆₀)_n@SWNT (peapod) samples were prepared by vapor diffusion method. We performed the high pressure Raman measurements on the peapod samples by using a Mao-Bell type diamond anvil cell (DAC). In the In situ high pressure experiments, the peapod samples were exposed under UV laser line irradiation. The polymerization of C₆₀ molecules in SWNT cave under both laser irradiation and pressure effects has been studied. The Raman spectra of the released samples from high pressure indicated that C₆₀s form one-dimensional orthorhombic polymer. For the Raman measurements, two different excitation wavelengths were used, 325 nm laser and 830 nm laser.

Abstract: This single-molecule C60 system with two atomic lines as left input electrode and right output electrode is calculated by simulation using the Green，s function method based on the density function theory. The characteristics of current transmission of single-molecule C60 which include I-V curve, current-temperature changing and transmission spectrum are given. The resonant switching is shown from the single-molecule C60 transmission spectrum, differential negative resistance (NDR) and the high ratio of current peak and current valley are also indicated from the I-V curve. The conclusions can be explained using band theory very well and finally the impact of temperature for current of this C60 single-molecule system is discussed etc.