Surfactant-intercalated clay films containing metal phthalocyanines

Abstract

We previously showed that clay-surfactant films containing metal phthalocyanines catalyze electrochemical reductive dechlorinations. Cobalt(I1) phthalocyanine (CoIIPc) was a much better catalyst than the corresponding iron complex. This paper reports studies of these catalytic films by spectroscopic, X-ray, and electron microscopic methods. Scanning electron microscopy cross sectional images of films of didodecyldimethylmmonium bromide, clay, and CoIIPc were considerably different from the stacked layers observed for pure composites. Previously observed phase transitions are characteristic of surfactant bilayers. The general morphology of these films appears to feature a heterogeneous mixture of CoIIPc crystals and surfactant bilayers intercalated between clay layers. Electronic spectra and X-ray diffraction patterns suggest that iron phthalocyanine (FeIIPc) is present in oxidized forms in these films. CoIIPc films are better dechlorination catalysts partly because CoIIPc remains intact in the films, while FeIIPc is decomposed.

Intercalation of cationic phthalocyanines into layered titanates and control of the microstructuresElectronic supplementary information (ESI) available: CHN analytical data and amounts of PA and Pc intercalated in Ti3O7 (Table S1), and XRD patterns of products derived from H2Ti3O7 (Fig. S1). See http://www.rsc.org/suppdata/jm/b2/b210237b/

“…In the spectrum of the DMSO solution of FePc 1 , a peak and a shoulder due to the p-p * transition are observed at 654 and 600 nm, respectively. 16 In the spectra of the suspensions of FePc-TSM and FePc-Ti 2 2 x/4 % x/4 O 4 , the peak at 654 nm is predominant, indicating that FePc 1 is mainly present in the monomeric state. Based on the XRD data and visible absorption spectra, the intercalated FePc 1 is monomeric and arranged with the molecular axis parallel to the layers.…”

“…13 In particular, immobilization of dyes and formation of their aggregated states are of importance for controlling the properties of materials, such as the photosensitization of TiO 2 14 and the photoconductivity of the aggregates. 15 Although intercalation of phthalocyanines into layered materials has been investigated using clays, layered double hydroxides, layered perovskites, and so on, [16][17][18][19][20][21][22] only the formation of dimers in the galleries [16][17][18] has been investigated and there have been no studies on the formation of aggregates.…”

Ultrathin hybrid films of clay minerals

“…Both techniques give rather well-defined thin films with thicknesses in the range of a few tens of nanometers (spincoating) 11,12 to a few tens of micrometers (dropcasting). [13][14][15][16][17][18][19] In this review we restrict our discussion to L-b-L assembly and the LB technique because they allow film construction with thicknesses down to elementary clay mineral platelets. The thickness of a clay monolayer without adsorbed molecules is then 0.96 nm.…”

Core–shell nanocluster films of hemoglobin and clay nanoparticle: Direct electrochemistry and electrocatalysis

“…The clay films cast from aqueous dispersions gave a basal plane spacing of 13.8 Å , larger than the value of 10.2 Å for clay films cast from organic solvent [50]. This was probably caused by water intercalation between the clay layers in the former situation [23].…”