This article highlights recent advances in the newly emerging field on the nanostructuration of molecular magnets using porous substrates.

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Co-Mo-TiO 2 composite and Co-Mo alloy thin films were galvanostatically electrodeposited and their HER electrocatalytic properties assessed, in order to better understand the role of added micro-scale TiO 2 particles. During electrodeposition, the metal ion partial current densities were enhanced with the inclusion of the particle, resulting in a higher current efficiency but with no change in the HER side reaction. However, a significant change in the HER occurred in a 1 M NaOH electrolyte with the composites compared to their alloy counterparts. The deposit surface area was examined in a ferricyanide electrolyte to assess the HER exchange current density and overpotential in the alkaline electrolyte. The HER exchange current density with composites containing TiO 2 exhibited values nearly 1 mA/cm 2 , approximately 3 times higher than the Co-Mo alloys. The overpotential at a cathodic current density of 10 mA/cm 2 , ƞ 10 , of the Co-Mo-TiO 2 composites was low, with the best value reaching 68 mV, which is 40 mV smaller than their alloy counterparts. The Tafel slope of all deposits with TiO 2 were similar in the range of 70-75 mV/decade, indicating that not one step in a Volmer-Heyrovsky mechanism is rate determining.

A composite electrode composed of electrodeposited, nickel-iron nanostructured clusters onto a glassy carbon (GC) disk electrode was used as a working electrode to detect methylene blue at concentrations below 10 μM. The Ni-Fe clusters were prepared by pulse electrodeposition and a lateral composition variation was observed reflective of a local pH change across the Ni-Fe feature. The applied potential for the detection of MB at a pH of 4 was determined through voltammetry and demonstrated using chronoamperometry and electrochemical impedance spectroscopy (EIS) where the adsorption of MB influenced both the capacitance, C, and ohmic resistance, Rs. A peak present in it1/2 vs t chronoamperometry plots decreased with lower MB bulk concentration, while in contrast, the RsC parameters determined from equivalent circuit models of EIS had the opposite behavior having a larger signal with lower MB concentration, and hence providing a way to increase the detection signal at lower MB concentration.