Thick, 3-14 mil, free-standing polypyrrole films incorporating a large variety of anion "dopants" were anodically deposited from aqueous electrolytes. Four-point probe conductivity and x-ray diffraction measurements were made and compared. Aromatic and very large amphiphilic sulfonate dopants provided the highest conductivities (up to 120 S cm-l), stabilities, mechanical properties, and apparent order. The dodecylbenzenesulfonate system was the most stable, being unaffected by even concentrated aqueous ammonia. A qualitative voltammetric technique which probes the relative order in as-deposited thin films is introduced.

A series of freestanding conducting polypyrrole and poly‐3‐methylthiophene films was prepared and examined by x‐ray diffraction and transmission electron microscopy (TEM). The degree of order observed in polypyrroles was highly dependent upon the incorporated “dopant” anions and also on deposition conditions. Examination of a large variety of dopant systems showed that substituted benzenesulfonate and long aliphatic chain monoanions imparted the highest order, and chemically prepared polypyrroles were less ordered than their electrochemical counterparts. Doped poly‐3‐methylthiophene exhibited comparable order, yet was less flexible in its ability to incorporate large dopant anions. Crystalline phases were detected by electron diffraction in some polymer systems.

Multilayered foils with 10% Cu-90% Ni and ultrathin (9-2000A) layers have been fabricated by electrodeposition. The anodic passivity of Ni and the irreversibility of the Ni/Ni z+ reaction permit alternate deposition of each metal layer from a common electrolyte. SEM, TEM, and x-ray diffraction analysis indicate discrete layer formation and a (100) textured structure. A maximum in the tensile strength and electrical resistivity of these foils was detected at a wavelength of 200A (20A Cu + 180A Ni). The maximum tensile strength obtained (1900 MPa) is over 3 and 4.5 times greater than that for homogeneous Ni and Cu foils and exceeds the maximum value reported for vacuum deposited foils by 70%.Ultrastructured materials, comprising alternating microlayers of two or more materials, exhibit greatly altered properties relative to the components. The periodic lattice distortion introduced by the artificial composition modulation can generate materials with unique and sometimes enhanced physical and chemical properties. Anomalous effects, which include a maximum at a wavelength (~) of -20A for mechanical and transport properties, have been observed for bimetallic vacuum deposited layered composites (1-3).Electrodeposition has been shown to be a viable technique for fabrication of multilayered composites with discrete layers (4-9). Bimetallic multilayered structures can be conveniently fabricated by alternate reduction of the metal ions from a common electrolyte containing both metals in a ratio of about 1(noble metal):100 (4-9). Electrodeposited Cu-Ni multilayered composites exhibited enhanced tensile strength as the Cu + Ni layer thickness (or k) was decreased to 100 nm (6). This paper explores the dependence of tensile strength and resistivity as the layer thickness approaches atomic dimensions. The deposition technique has been extended to permit fabrication of free-standing Cu-Ni composites with an order of magnitude thinner layers. The deposit properties are evaluated by x-ray diffraction, SEM/EDX, TEM, tensile testing and electrical conductivity measurements. ExperimentalThe Cu-Ni foils were electrodeposited on an Inconel rotating cylinder from a Ni-sulfamate bath (80 g/liter Ni, 40 g/ liter H3BO3, 0.15 g/liter Na-dodecyl sulfate) to which CuSO4 was added as required. Bath pH was 3.8. A 0.5 ~m thick Ni basal was initially deposited to eliminate structural patterns of the polycrystalline substrate. Cu and Ni layers were then alternately deposited with synchronous modulation of the electrode rotation speed and the deposition current (or potential). The electrode rotation rate, current density, periodicity, and atomic percent of the respective metals were varied with a HP-9826 computer interfaced with a PAR-173 potentiostat/galvanostat. Cathode dimensions and cell configuration, and other plating parameters were as described in Ref. (6). The foil thickness, which ranged from 25-50 ~m, was measured with a digimatic micrometer. Individual layer thickness was determined from the amount of charge passed and verified using a...

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Components 2'Ale hem. shift (ppm) Conc (m/o) A1Ch .2THF 64 56 AICI4-103 44 Original components: 1.3 tool liter-~ A1Cls + 0.3 real liter --1 LiA1H~ h'l THF.Table IV. Concentration of species in the replenlshed bath Components ~A1 chem. shift (ppm) Concentration (m/o) A1Cls 9 2THF 64 74 I 38 A1HC12 9 2THF 76 L. 86 AICh-103 22 AII-ICIs-114 4 * Electrochemical Society Active Member.