Synthesis, Characterization And Photoelectric Property Of Fullerene-Phosphine Metal Complex

Fullerene-metal complex exhibited the high potential on the application of nonlinear optics and photoelectric conversion, catalysis, superconductivity. Many kind of fullerene complex were synthesized, and most of the complex contained the phosphine ligand. At present, platinum and palladium fullerene complex of phosphine ligand has aroused people's enormous interest because of their stability and the potential application. So, the related research of fullerene-metal complex is becoming the research focus of fullerene chemistry. Therefore, to synthesize the new kind of fullerene-metal complex and to study the properties have important theoretical and realistic meaning.In this paper, selecting three extensively used bisdentate phosphine ligands (dppp, dpppe, BINAP) as raw materials, six kinds of fullerene-phosphine metal complex, C₆₀Pd(dppp),C₆₀Pt(dppp),C₆₀Pd(dpppe),C₆₀Pt(dpppe),C₆₀Pd(BINAP),C₆₀Pt(BINAP),were synthesized by ligand-substituted method. First, synthesizing the low valent platinum and palladium complex of bisdentate phosphine ligand, and then using the C60 substitute the partial phosphine ligand to form the result products. The prpoducts were characterized by MS, elemental analysis, UV-Vis, IR and XPS, and systemically analysed by using the related theories. Take C₆₀Pt(BINAP) as an example, the data are as follows: MS:1538.1; EA: C 79.95, H 2.16. Found: C 81.14, H2.08; UV-vis (THF):λmax245,332, 446, 647; IR (KBr disk):ν_C60 521, 575, 1185, 1435cm^-1. Combining these results with systematically theoretical analysis, it demonstrated that the six kind of new complexes were synthesized, and C60 formed theη²-fullerence metal complex withσ-Ï€back-bonding.These complexes and GaAs electrode were used to build up the composite eletrode, which formed n+n heterojunction. Through determination of the photovoltaic effect of the composite eletrode in the photochemistry cell, the photoelectricity of the six compounds was investigated. The influence of many factors, such as the medium electrode couple, the thickness of the complex film, center metal ion and the structure of phosphine ligand, on the photoelectricity were also investigated and analyzed. The results showed that: the fullerene-phosphine metal complex exhibited high photoelectric conversion property, especially under the conditions of BQ/H_2Q and I3-/I2 redox couples, and 1～2μm of thickness of the film. Using fullerene-phosphine Pd complex, the maximum value of photovoltage was measured. It was found that the value of photovoltage of the fullerene-phosphine Pt complex showed great regularity. For the fullerene-phosphine metal complex containing the same central metal ions, the different bisdentate diphenylphosphine ligands showed little influence on the photochemical property.