N-doped, core–shell carbon nanotube–graphene nanoribbons are developed as novel substrates for anchoring Co3O4nanocrystals as bifunctional catalysts for oxygen electrochemistry.

Amorphous thin films of cobalt oxides with controlled nanostructures and compositions have been prepared by electrodeposition from a room temperature protic ionic liquid for water oxidation electrocatalysts. The electrochemical behaviour of Co 2+ has been studied in ethylammonium nitrate (EAN) using cyclic voltammetry and chronoamperometry. The electrodeposition of Co 2+ in EAN occurs at À0.95 V vs. Fc 0/+ , followed by hydrogen evolution reaction. The electro-oxidation of Co 2+ to Co 3+ is found to be a reversible process in dried EAN at E 1/2 ¼ 1.47 V vs. Fc 0/+ . The presence of water significantly affects the voltammetric behaviour of Co 2+ and the subsequent electrodeposition processes.Cobalt oxides nanostructures have been deposited onto glassy carbon and indium tin oxide (ITO)coated glass substrates by two routes, (i) controlled-potential deposition of Co, followed by spontaneous air oxidation and (ii) controlled-potential deposition of Co followed by anodic oxidation in the presence of water. SEM, EDX, XRD and XPS reveal that cobalt oxides of different morphologies and chemical compositions are formed on the surface of electrodes. The cobalt oxides films exhibit catalytic activity towards water oxidation reaction in neutral phosphate buffered solution with low overpotentials.

Hybrid semiconducting silver-tetracyanoquinodimethane (AgTCNQ) nanowires decorated with Ag nanoparticles have been synthesized at room temperature in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate. Hydroquinone was applied to reduce Ag þ and TCNQ to silver nanoparticles, and TCNQ À , respectively, under ambient conditions. AgTCNQ nanowires were formed via spontaneous electrolysis between Ag metal nanoparticles and TCNQ, and reaction between Ag þ and TCNQ À . Microscopic, spectroscopic, and X-ray characterizations all confirmed the formation of crystalline Ag nanoparticle-AgTCNQ nanowire hybrid structures. The ionic liquid was used as a reaction medium, but also as a stabilizing (or blocking) agent to control the nucleation and growth rate of AgTCNQ wires.