Dendrimer cyclic voltammograms

Frechet and co-workers [32] studied the ability of the dendrimer shell to provide site isolation of the core porphyrin moiety, using benzene-terminated dendrimers Zn[G-n]4P (i.e. 6). From the cyclic voltammograms in CH2C12, the interfacial electron transfer rate between the porphyrin core and the electrode surface decreased with increasing dendrimer generation. However, small molecules like benzyl viologen could still penetrate the shell of 6 to access the porphyrin core as observed from the quenching of porphyrin fluorescence. Their results also revealed that the dendritic shell did not interfere electrochemically or photochemically with the porphyrin core moiety. 

Figure 29 Cyclic voltammogram recorded at a platinum electrode in a CH2Cl2 solution of the illustrated 64Fc dendrimer. Scan rate 0.1 V s ...

Figure 5. Cyclic voltammograms of dendrimers (A) 6 and (B) 4, in solution of CHjCIjA). M TBAH, at a scan rate of 50 mV/s.

Figure 6. Cyclic voltammograms of a platinum disk-electrode modified with a film of the octanuclear dendrimer 2, measured in 0.1 M Bu NPFj/CHjClj. The surface coverage of electroactive ferrocenyl sites in the film is determined to be T = 2.01 x 10" mol cm . inset, scan rate dependence of the anodic peak current.

Figure 10. (A) Cyclic voltammograms for the dendrimer 6/glucose oxidase/carbon paste electrode, recorded at 1 mV/s in pH 7.0 phosphate buffer (with 0.1 M KCI)...

Figure 6.4 (a) Structural formula of the 1,2,3-triazole-linked dendrimer 4 containing nine ferrocene peripheral units (b) cyclic voltammogram of 4 without (1) and in the presence of... 

Figure 6.20 Cyclic voltammograms of the first (a) at 8000 V/s and second (b) at 140 V/s generation of dendrimers containing a hexaphenylbenzene core and 6 and 12 C60 units, respectively (THF in the presence of 0.3 M of tetrabutylammonium hexafluorophosphate as supporting electrolyte).74 Reproduced with permission from Ref. 74.

Figure 11.3 Cyclic voltammogram of the 243-ferrocenyl dendrimer ( 243-Fc ) in CH2CI2 solution containing 0.1 M [u-Bu4N][PF6] (a) in solution (10-4M) at lOOmV s-1 on the Pt anode (b) Pt anode modified with 243-Fc at various scan rates, dendrimer-free clear CH2CI2 solution. (Inset intensity as a function of scan rate the linearity shows the expected behavior of a modified electrode with a fully adsorbed dendrimer.)...

Figure 34 Cyclic voltammograms for ferrocene dendrimer 239 in (a) CH2CI2 (b) CH2Cl2/MeCN 5 1, and (c) as a film on a Pt electrode. Supporting electrolyte 0.1 M [Bu4N][PFe] scan rate lOOmVs (Reproduced with permission of The American Chemical Society from Cuadrado, C. M. etal., J. Am. Chem. Soc., 1997, 119, 7613.)...

A convergent synthesis of dendrimers 8.23 and 8.24, which possess interacting ferrocenyl units, by means of hydrosilylation reactions of the Si-H polyfunctiona-lized cores, has been described [45]. Cyclic voltammograms of these dendrimers exhibit two distinct oxidation waves separated by 0.19 and ca. 0.16 V for 8.23 (see Fig. 8.3) and 8.24, respectively. This electrochemical behavior is consistent with... 

Fig. 11 Cyclic voltammograms of PAMAM dendrimer with 64 pendant Ru(tpy) moieties (CH3CN/O.6 M NEt4BF4, Pt electrode with radius 5 pm, scan rates as indicated) (with kind permission ofWiley-VCH from Ref [40]).

Fig. S Cyclic voltammograms of dendrimers with zinc porphyrin in (1-4) core in TBAP-supporting electrolyte solution at 100 mV. Positive scans were performed in a CH2CI2 solution and negative scans were performed in DMF solution. From Ref 50 with permission.

Fig.6 Cyclic voltammograms of 1.0 mM solutions of dendrimers modified with ruthenium bis-terpyridyl in branches in a 0.1 M TBABF4/AN solution at 200 mV s . From Ref 64 with permission.

Fig. 8 Cyclic voltammograms at different sweep rates for a Pt disk electrode modified with a film of a silicon-based dendrimer (GO) possessing two ferrocenyl moieties linked to a silicon atom at each branch (eight ferrocenes in total) in a 0.1 M TBAH/CH2CI2 solution. Adapted from Ref. 75.

Shu et al. synthesized and characterized poly (aryl ether)-based dendrimers modified with 3, 6, 12, and 24 ferrocenyl moieties (GO, 1,2, and 3, respectively) [78]. CycKc and normal pulse voltammetry studies suggested that all ferrocenyl sites underwent electron transfer at the same potential in TBAH/CH2CI2 solution. The generations 0 and 1 dendrimers showed typical diffusional cyclic voltammograms, whereas generations 2 and 3 dendrimers showed that the oxidized form of the... 

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