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In this study, a fiber-shaped Co coating was electroplated on the Cu surface followed by the deposition of Pt crystallites using the galvanic displacement method. The electrochemical behavior of the prepared Co fiber and Pt nanoparticles decorated Co fiber catalysts were evaluated in order to provide insights into the electro-oxidation of N 2 H 4 in an alkaline media was performed using cyclic voltammetry and chrono-techniques. The influence of Co fiber /Cu and PtCo fiber /Cu as the anode electrocatalyst on the performance of direct N 2 H 4 -H 2 O 2 fuel cell was investigated at different temperatures. The deposition of a small amount of Pt crystallites, in the range of 5 μg Pt cm -2 to 29 μg Pt cm -2 , significantly improved the performance of the fiber-shaped Co catalyst for the electro-oxidation of N 2 H 4 in an alkaline medium. The measured N 2 H 4 oxidation current densities at −0.2 V are approximately 5-6 times larger for different PtCo fiber /Cu catalysts, compared with that of a pure Co fiber /Cu. The single N 2 H 4 -H 2 O 2 fuel cell results showed that the highest peak power density of 219.8 mW cm -2 for the N 2 H 4 -H 2 O 2 fuel cell was obtained with the PtCo fiber /Cu catalyst that has the Pt loading of 28.7 μg Pt cm -2 .

The present work is focused on the investigation of the oxidation of BH 4 − ions in an alkaline solution on a low-cost ZnCo alloy deposited on the Ti surface. The Co and ZnCo alloy coatings were deposited on the Ti surface via electrodeposition. The morphology, structure and composition of the prepared catalysts were examined by FESEM and EDX. The activity of the fabricated catalysts was investigated toward the oxidation of BH 4 − ions by means of cyclic voltammetry and chronoamperometry. It has been determined that Co/Ti and ZnCo/Ti catalyze the oxidation of H 2 generated by the catalytic hydrolysis of BH 4 − and direct oxidation of BH 4 − ions. The H 2 oxidation current densities measured on both the catalysts are rather close and reach up to 60 mA cm −2 , whereas the borohydride oxidation current densities are ∼3-4 times higher at −0.2 V on ZnCo/Ti than those obtained on Co/Ti and Zn/Ti.

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This work presents the investigation of the electrochemical oxidation of hydrazine and sodium borohydride ions in alkaline solutions on the Au nanoparticles modified ZnCo coating surface, which was deposited on the titanium substrate (termed as AuZnCo/Ti). The AuZnCo/Ti catalysts were prepared via a facile electrochemical deposition technique followed by a simple and low-cost galvanic displacement. Scanning electron microscopy, energy dispersive X-ray analysis and inductively coupled plasma optical emission spectroscopy were used for characterization of the prepared catalysts surface morphology, structure and composition, whereas their electrocatalytic behaviour was investigated for the electrochemical oxidation of hydrazine and sodium borohydride in an alkaline medium using cyclic voltammetry. It has been determined that the AuZnCo/Ti catalysts with Au loadings of 31, 63 and 306 µg cm–2 show enhanced catalytic activity towards the electrochemical oxidation of both hydrazine and sodium borohydride as compared to that of the ZnCo/Ti catalyst.