With laser flash photolysis, UV visible absorption spectroscopy and transient absorption spectroscopy techniques, the quenching rates of excited state of [Au 2 ( μ dmpm) 3](ClO 4) 2 by alkyl halides were measured, th...With laser flash photolysis, UV visible absorption spectroscopy and transient absorption spectroscopy techniques, the quenching rates of excited state of [Au 2 ( μ dmpm) 3](ClO 4) 2 by alkyl halides were measured, the steady state photoreaction of [Au 2( μ dmpm) 3](ClO 4) 2 and CHCl 3 was investigated, respectively. The mechanism of C C coupling reaction from benzyl chloride with Au(Ⅰ) phosphine bridge complex as photocatalyst was explored. It was found that [Au 2( μ dmpm) 3](ClO 4) 2 lost a dmpm ligand easily to give [Au 2( μ dmpm) 2](ClO 4) 2, the latter played the key role in the photocatalytic reaction. Bibenzyl was produced by the combination of two benzyl radicals or by the nucleophilic reaction of benzyl anion and benzyl chloride.展开更多
In this paper, we report a high-perfornmnce P3HT/PCBM bulk-heterojunction solar cell with a power conversion efficiency of 4.85% fabricated by adjusting the polymer crystallinity and nanoscale phase separation using a...In this paper, we report a high-perfornmnce P3HT/PCBM bulk-heterojunction solar cell with a power conversion efficiency of 4.85% fabricated by adjusting the polymer crystallinity and nanoscale phase separation using an ultrasonic irradiation mixing approach for the polymer. The grazing incidence X-ray diffraction, UV/Vis spectroscopic, and atomic force microscopic measurement results for the P3HT/PCBM blend films reveal that the P3HT/PCBM film fabricated by ultrasonic irradiation mixing of the P3HT and PCBM solutions for 10 min has a higher degree of crystallinity, a higher absorption efficiency, and better phase separation, which together account for the higher charge transport properties and photovoltaic cell performance.展开更多
A novel crown ether, 2,3-naphtho-10-aza-15-crown-5 (NAC) was synthesized.This compound does not show strong fluorescence and phosphorescence due to photoinducedintramolecular electron transfer from the nitrogen lone p...A novel crown ether, 2,3-naphtho-10-aza-15-crown-5 (NAC) was synthesized.This compound does not show strong fluorescence and phosphorescence due to photoinducedintramolecular electron transfer from the nitrogen lone pair of electrons to the singlet excitedstate of the naphthalene chromophore. Complexation with heavy-metal ions results in the quenching ofthe fluorescence and enhancement of the phosphorescence significantly. These observations wereinterpreted in terms of the binding interactions, between the nitrogen lone pair electrons and themetal cation, which prevent photoinduced intramolecular electron transfer, and the heavy-atomeffects which induce quenching of the fluorescence and enhancement of the phosphorescence. Theseazacrown and heavy-metal-based systems could be useful as potential chemical sensors and molecularphotonic devices.展开更多
文摘With laser flash photolysis, UV visible absorption spectroscopy and transient absorption spectroscopy techniques, the quenching rates of excited state of [Au 2 ( μ dmpm) 3](ClO 4) 2 by alkyl halides were measured, the steady state photoreaction of [Au 2( μ dmpm) 3](ClO 4) 2 and CHCl 3 was investigated, respectively. The mechanism of C C coupling reaction from benzyl chloride with Au(Ⅰ) phosphine bridge complex as photocatalyst was explored. It was found that [Au 2( μ dmpm) 3](ClO 4) 2 lost a dmpm ligand easily to give [Au 2( μ dmpm) 2](ClO 4) 2, the latter played the key role in the photocatalytic reaction. Bibenzyl was produced by the combination of two benzyl radicals or by the nucleophilic reaction of benzyl anion and benzyl chloride.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60871007)
文摘In this paper, we report a high-perfornmnce P3HT/PCBM bulk-heterojunction solar cell with a power conversion efficiency of 4.85% fabricated by adjusting the polymer crystallinity and nanoscale phase separation using an ultrasonic irradiation mixing approach for the polymer. The grazing incidence X-ray diffraction, UV/Vis spectroscopic, and atomic force microscopic measurement results for the P3HT/PCBM blend films reveal that the P3HT/PCBM film fabricated by ultrasonic irradiation mixing of the P3HT and PCBM solutions for 10 min has a higher degree of crystallinity, a higher absorption efficiency, and better phase separation, which together account for the higher charge transport properties and photovoltaic cell performance.
文摘A novel crown ether, 2,3-naphtho-10-aza-15-crown-5 (NAC) was synthesized.This compound does not show strong fluorescence and phosphorescence due to photoinducedintramolecular electron transfer from the nitrogen lone pair of electrons to the singlet excitedstate of the naphthalene chromophore. Complexation with heavy-metal ions results in the quenching ofthe fluorescence and enhancement of the phosphorescence significantly. These observations wereinterpreted in terms of the binding interactions, between the nitrogen lone pair electrons and themetal cation, which prevent photoinduced intramolecular electron transfer, and the heavy-atomeffects which induce quenching of the fluorescence and enhancement of the phosphorescence. Theseazacrown and heavy-metal-based systems could be useful as potential chemical sensors and molecularphotonic devices.
