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Two BODIPY‐C60‐peptide assemblies were synthesized by CuAAC reactions of BODIPY‐C60 dyads and a helical peptide functionalized with a terminal alkyne group and an azide group, respectively. The helical peptide within these assemblies was functionalized at its other end by a disulfide group, allowing formation of self‐assembled monolayers (SAMs) on gold surfaces. Characterizations of these SAMs, as well as those of reference molecules (BODIPY‐C60‐alkyl, C60‐peptide and BODIPY‐peptide), were carried out by PM‐IRRAS and cyclic voltammetry. BODIPY‐C60‐peptide SAMs are more densely packed than BODIPY‐C60‐alkyl and BODIPY‐peptide based SAMs. These findings were attributed to the rigid peptide helical conformation along with peptide‐peptide and C60‐C60 interactions within the monolayers. However, less dense monolayers were obtained with the target assemblies compared to the C60‐peptide, as the BODIPY entity likely disrupts organization within the monolayers. Finally, electron transfer kinetics measurements by ultra‐fast electrochemistry experiments demonstrated that the helical peptide is a better electron mediator in comparison to alkyl chains. This property was exploited along with those of the BODIPY‐C60 dyads in a photo‐current generation experiment by converting the resulting excited and/or charge separated states from photo‐illumination of the dyad into electrical energy. [ABSTRACT FROM AUTHOR]

The characterization of quasi-hemispherical Pt electrodes of nanometer dimensions (radius 2-150 nm), prepared by electrophoretic coating of etched Pt wires with poly(acrylic acid), is described. The goals of these experiments are to estimate the accuracy of using steady-state voltammetric limiting currents ([i.sub.lim]) in determining the true electrode area and to develop new electrochemical methods for rapidly screening individual electrodes for nonideal geometries. Electrochemical active areas were determined by measuring the electrical charge (Q) associated with oxidation of adsorbed bis (2,2'-bipyridine)chloro(4,4'-trimethylenedipyridine)osmium(II) in fast-scan voltammetric measurements (scan rate 1000 V/s). Voltammetric peaks corresponding to oxidation of as few as ~7000 molecules (~11 zmol) at individual electrodes are reported, allowing precise measurement of electrode areas as small as [~10.sub.-10] [cm.sub.2]. A plot of [i.sup.lim] (for a soluble redox species) versus [Q.sup.1/2] (for an adsorbed redox species), constructed from [i.sub.lim]-[Q.sup.1/2] data pairs obtained as a function of the electrode radius, is shown to be linear if the electrode geometry is independent of electrode radius; departure of experimental values from the straight-line plot is a diagnostic indicator of a nonideal electrode geometry. The results indicate that ~50% of the electrodes prepared by the electrophoretic polymer-coating procedure are quasi-hemispherical, the remaining being recessed slightly below the polymer coating. The heterogeneous electron-transfer rate constant for the oxidation of the ferrocenylmethyltrimethylammonium cation in [H.sub.2]O/ 0.2 M KCI was also determined from steady-state voltammetry using the method of Mirkin and Bard and found to be [4.sub.8][+ or -] 3.2 cm/s with [alpha]=0.[6.sub.4] [+ or -] [0.1.sub.5].

A convenient method for the generation of [CpFe(CO)(sub 2)](super -) by the photochemical reduction of [CpFe(CO)(sub 2)](sub 2) by a unique organic two-electron donor, that is, an NAD (nicotinamide adenine dinucleotide) dimer analogue 1-benzyl-1,4-dihydronicotinamide dimer [(BNA)(sub 2)](super 18,19) is reported. The studies suggest that the photochemical generation of [CpFe(CO)(sub 2)](super -) by (BNA)(sub 2) proceeds through photoinduced electron transfer from the triplet excited state of (BNA)(sub 2) to [CpFe(CO)(sub 2)](sub 2).