Spectroscopic and Electrochemical Characterization of Langmuir−Blodgett Films of (2,3,9,10,16,17,23,24-Octakis((2-benzyloxy)ethoxy)phthalocyaninato)copper and Its Metal-free Analogue

Abstract

Spectroscopic, electrochemical and spectroelectrochemical, and scanning probe microscopic characterization of thin films of (2,3,9,10,16,17,23,ethoxy)phthalocyaninato)copper, and its dihydrogen analogue, in contact with aqueous electrolytes is described. These materials form highly ordered Langmuir-Blodgett (LB) thin films, where the phthalocyanine (Pc) rings orient with the plane of the ring nearly perpendicular to the compression direction on the LB trough. The resultant thin films show remarkable mechanical stability on the trough, and atomic force microscopy studies show that the transferred thin films, in their fully compressed states, consist of stable bilayers of the Pc. X-ray diffraction studies indicate partial overlap of the benzyl-terminated side chains in adjacent Pc columns. While the DMF solution electrochemical behavior of these molecules showed a single quasi-reversible oxidation process, LB thin films showed two poorly resolved oxidation processes. Two electrochemically distinct domains in these thin films are indicated, which are a function of the aggregation behavior of these materials, and result from electrochemically driven changes in film morphology.

Interfacial Microstructure Function in Organic Light-Emitting Diodes: Assembled Tetraaryldiamine and Copper Phthalocyanine Interlayers

“…The densely crosslinked nature of TPD-Si 2 films is evident in the relatively large separation of oxidative and reductive peaks (200 mV), suggesting kinetically hindered oxidation/reduction processes with retarded counterion mobility. [22] That TPD-Si 2 film coverage on ITO is conformal and largely pinhole-free is supported by studies using a previously described ferrocene probe technique. [23] The lack of significant current flow near the formal potential for ferrocene oxidation at a TPD-Si 2 -coated ITO working electrode indicates suppression of ferrocene oxidation, consistent with largely pinhole-free surface coverage.…”

Monolayers and Langmuir-Blodgett films of crown-substituted phthalocyanines

“…6, curve 1) contains two Q bands in the visible region char acteristic of solutions of phthalocyanine ligands. [25][26][27][28] A decrease in the solution concentration by two orders of magnitude (curve 2) neither changes the spectrum shape, nor shifts the characteristic bands. The green color of the solution also indicates that the ligand exists in the mono (Fig.…”

Conjugated compounds in supramolecular informational systems: A review

“…Recently, the effort of many scientists working on enhancement of the electric properties of phthalocya nine films and the efficiency of their production has been directed toward synthesis of octa substituted amphiphilic derivatives [331][332][333][334][335][336][337][338]. It was shown that such compounds can form true monolayers consisting of stacking aggregates and existing upon compression up to pressures of no more than 10-15 mN/m.…”