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Electrodeposition of Co–W alloy coatings has been carried out with DC and PC using gluconate bath at different pH. These coatings are characterized for their structure, morphology and chemical composition by X‐ray diffraction, field emission scanning electron microscopy, differential scanning calorimetry and X‐ray photoelectron spectroscopy (XPS). Alloy coatings plated at pH8 are crystalline, whereas coatings electrodeposited at pH5 are nanocrystalline in nature. XPS studies have demonstrated that as‐deposited alloy plated at pH8 with DC contain only Co2+ and W6+ species, whereas that alloy plated at pH5 has significant amount of Co0 and W0 along with Co2+ and W6+ species. Again, Co2+ and W6+ are main species in all as‐deposited PC plated alloys in both pH. Co0 concentration increases upon successive sputtering of all alloy coatings. In contrast, mainly W6+ species is detected in the following layers of all alloys plated with PC. Alloys plated at pH5 show higher microhardness compared to their pH8 counterparts. Copyright © 2013 John Wiley & Sons, Ltd.

Hydrogen is a clean energy carrier and highest energy density fuel. Water gas shift (WGS) reaction is an important reaction to generate hydrogen from steam reforming of CO. A new WGS catalyst, Ce 1−x Ru x O 2−δ (0 ≤ x ≤ 0.1) was prepared by hydrothermal method using melamine as a complexing agent. The Catalyst does not require any pre-treatment. Among the several compositions prepared and tested, Ce 0.95 Ru 0.05 O 2−δ (5% Ru 4+ ion substituted in CeO 2) showed very high WGS activity in terms of high conversion rate (20.5 μmol.g −1 .s −1 at 275 • C) and low activation energy (12.1 kcal/mol). Over 99% conversion of CO to CO 2 by H 2 O is observed with 100% H 2 selectivity at ≥ 275 • C. In presence of externally fed CO 2 and H 2 also, complete conversion of CO to CO 2 was observed with 100% H 2 selectivity in the temperature range of 305-385 • C. Catalyst does not deactivate in long duration on/off WGS reaction cycle due to absence of surface carbon and carbonate formation and sintering of Ru. Due to highly acidic nature of Ru 4+ ion, surface carbonate formation is also inhibited. Sintering of noble metal (Ru) is avoided in this catalyst because Ru remains in Ru 4+ ionic state in the Ce 1−x Ru x O 2−δ catalyst.

Direct current electrodeposition of Co – P alloy coatings were carried out using gluconate bath and they were characterized by employing techniques like XRD, FESEM, DSC and XPS. Broad XRD lines demonstrate the amorphous nature of Co – P coatings. Spherical and rough nodules are observed on the surface of coatings as seen from FESEM images. Three exothermic peaks around 290, 342 and 390°C in DSC profiles of Co – P coatings could be attributed to the crystallization and formation of Co 2 P phase in the coatings. As-deposited coatings consist of Co metal and oxidized Co species as revealed by XPS studies. Bulk alloy P ( P δ-) as well as oxidized P ( P 5+) are present on the surface of coatings. Concentrations of Co metal and P δ- increase with successive sputtering of the coating. Observed microhardness value is 1005 HK when Co – P coating obtained from 10 g L-1 NaH 2 PO 2 is heated at 400°C that is comparable with hard chromium coatings.

The design of platinum-group-metal-free (PGM-free) electrocatalysts with appreciable activity and durability toward the oxygen reduction reaction (ORR) in acidic environments is a big challenge. Here, we report an efficient oxygen reduction activity of a Co-encapsulated nitrogen-doped carbon with nanofiber networks and its ionic liquid-modified interface in an acidic medium. The robust structure of the nanofibers embedded on a rigid framework derived from a zeolitic imidazole framework (ZIF-67) delivers promising activity and durability to the catalyst comparable to the state-of-the-art Pt/C. The ionic-liquid-modified catalyst shows a half-wave potential of 0.71 V vs RHE in oxygen-saturated 0.5 M H2SO4 along with activity reduction by only 11 mV (E 1/2) after 5000 cycles of the accelerated durability test. The catalyst also retains 71% of its original current during the short-term durability test. Furthermore, the electron transfer number and H2O2 yield of the catalyst during the ORR approaches 3.88–3.90 and 5.9–4.8% in the potential range 0.4–0.7 V vs RHE. The ORR performance of the ionic-liquid-modified catalyst is superior among all ionic liquid-based non-PGM catalysts reported so far in acidic media.

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Ru 4+ Ion in CeO 2 (Ce 0.95 Ru 0.05 O 2-δ ): A Non-Deactivating, Non-Platinum Catalyst for Water Gas Shift Reaction. -Ce0.95Ru0.05O2-δ is hydrothermally prepared from an aqueous solution of Ce(NH4)2(NO3)6, RuCl3, and melamine as a complexing agent (autoclave, 200°C, 24 h). The material shows very high water gas shift activity in terms of high conversion rate and low activation energy. Over 99% conversion of CO to CO2 by H 2 O occurs with 100% H 2 selectivity at ≥ 275°C. Even in the presence of externally fed H2 and CO2, almost complete conversion of CO to CO2 with 100% H2 selectivity occurs in the temperature range 305-385°C. Due to the absence of carbonate and formate formation, there is no deactivation of the catalyst for the water gas shift reaction.-(SINGH, P.; MAHADEVAIAH, N.; PARIDA, S.; HEGDE*, M. S.; J. Chem. Sci. (Bangalore, India) 123 (2011) 5, 577-592 ; Solid State Struct. Chem. Unit, Indian Inst. Sci.,

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