Electrochemical Properties of Redox-active Tetrathiafulvalene and Fullerene C_(60)-functionalized Gold Nanoparticles, and Their Nanocomposite Films-modified Electrodes

摘要

電子ドナーのテトラチアフルバレンおよび電子アクセプターのフラーレンC_(60) を含む酸化還元活性金ナノ粒子（TTF-Au, C_(60)-Au）は，オクタンチオール保護金ナノ粒子とテトラチアフルバレンチオールあるいはフラーレンC_(60)チオールとの反応により合成した。TTF-Auコロイド溶液に金電極を浸漬するこにより電気化学的に安定な金ナノ粒子膜が金表面上に生成した。また，C_(60)-Auも安定な金ナノ粒子膜が金電極表面上に生成し，その金ナノ粒子膜修飾金電極は明瞭な2電子還元波を示した。これとは対照的に，フラーレンC_(60)チオール自己集合単分子膜修飾金電極は明瞭な2電子還元波を示さない。TTF-AuおよびC_(60)-Auのような電子ドナーおよびアクセプター修飾金ナノ粒子を含むナノ複合膜修飾電極を作成し，電気化学的性質について調べた。%Redox-active gold nanoparticles containing tetrathiafulvalene as an electron donor (TTF-Au nanoparticles) and fullerene C_(60) as an electron acceptor (C_(60)-Au nanoparticles) have been prepared by the reaction of octanethiol-stabilized gold nanoparticles with a tetrathiafulvalenyl-monothiol and a fullerene C_(60)-terminated alkanethiol. Immersion of a gold electrode in a solution of the colloidal TTF-Au nanoparticles deposited the colloid films of them on the electrode surface, which were remarkably stable under repeated electrochemical cycling. Analogously, the self-assembly of C_(60)-Au on planar gold surface led to the formation of the nanoparticle films which showed two distinct reversible reduction/oxidation waves and significant electrochemical stability. The electrochemical responses for the C_(60)-Au nanoparticle films and self-assembled monolayers of the C_(60)-thiol adsorbed on gold electrodes are significantly different. The nanocomposite films containing electron-donor and -acceptor functions such as TTF-Au and C_(60)-Au can be characterized by cyclic voltammetry.