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In+As+Sb alloys have been deposited onto Ni and Ti cathodes from tartaric acid solutions at pH 2. Homogeneous deposits of composition suitable for achieving InAs x Sb 1−x can be obtained from this medium. The As-to-Sb ratio can be controlled by properly selecting solution composition and deposition potential. X-ray photoelectron spectroscopy and X-ray diffraction analyses show that formation of III–V compounds occurs at room temperature. In reacts preferentially with As rather than with Sb, but crystalline phases formed at room temperature are Sb-rich. After annealing the In+As+Sb alloys at 250°C, the composition calculated from cell parameters appears similar to that measured by energy-dispersive X-ray analysis, suggesting that the entire deposit has been converted into the InAs x Sb 1−x crystalline phase.

The codeposition of In + As alloys has been investigated as a preliminary step for the preparation of thin polycrystalline InAs and InAs x P 1− x films. Alloys of composition ranging from large excess In to excess As could be obtained by a suitable choice of bath and deposition conditions. Stoichiometric 1:1 deposits have been converted to InAs by simple thermal treatment. In + As alloys with excess In annealed under PH 3 flow resulted in deposits consisting of two phases, an InAs x P 1− x phase with x in the range 0.25 to 1 and almost pure InP. Photoelectrochemical investigations showed that only the latter species was photoactive.

Anodically produced composites in which both the matrix and the dispersed phase are metal oxides (e.g. PbO2/Co3O4) are active electrocatalytic materials for the oxygen evolution reaction.

PbO2+CoOx composites have been deposited by anodisation of sulphamate solutions containing Pb2+ and Co2+ ions. The effect of experimental variables, like total Co2++Pb2+ concentration, Co2+/(Co2++Pb2+) ratio, potential, pH and angular speed of the anode, on the deposit composition has been investigated. The results are discussed according to the theories developed for the cathodic deposition of alloys, concluding that the system conforms to the trends typical of irregular deposition. XRD and XPS analyses have shown that the deposits are amorphous, but have not allowed to fully elucidate the nature of the Co containing compound(s) codeposited with PbO2. When used as anodes for oxygen evolution in aqueous NaOH, the PbO2+CoOx composites exhibit Tafel slopes of ca. 60 mV decade−1 and a reaction order of 1 with respect to OH−. Their overpotential is similar to that of PbO2+Co3O4 composites prepared by anodisation of suspensions. A marked activation of the PbO2+CoOx electrodes, during ca. 3 days of continuous oxygen evolution, is explained as the result of an increase of the Co surface concentration, as shown by XPS and impedance data.

Composite oxides of Pb and Ru have been deposited on Ti rotating disc electrodes and tested as anode materials for the oxygen evolution reaction (oer) from aqueous sulfuric acid. The composite oxides have been anodically deposited according to two different procedures: (i) the electrolysis of suspensions of RuO2 particles in Pb2+-containing electrolytes, or (ii) the electrolysis of solutions containing both Pb2+ and Ru3+. Both procedures are essentially successful, as the passivation of Ti (previously etched in aqueous HF) does not prevent oxide deposition. The former route leads to more active materials than the latter. Considering the oer overpotential and service life, the performance of these layers deposited on Ti is comparable to or better than those of oxides grown on a noble substrate (described in a previous paper).

After briefly summarizing the most common reactions used in the chemical synthesis of polyoxyphenylenes, this paper reviews the electrochemical polymerization of phenols for metal protection. It also describes how the reaction media, sometimes in unexpected ways, influence the chemical composition of the coatings and the status of the metal surface. The role of the adsorption of monomers and other components of electrolysis baths is discussed on the basis of in situspectroelectrochemical data. Lastly, it is shown that the adhesion between coatings and substrates may be influenced by acting either on the metal surface or on the polymer layer; adhesion is of primary importance in determining the rate of degradation of coatings exposed to a corrosive medium.