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This work reports the electrocatalytic activity of the AuCeO2/C and Au/C catalysts toward oxidation reaction of alcohols: methanol, ethanol, ethylene glycol, and glycerol in an alkaline medium. Gold nanoparticles (AuNPs)...

In this study a series of PtRuCo/GR with the different molar ratios were prepared by microwave-assisted heating of the reaction mixture consisting of H2PtCl6, RuCl3, CoCl2 and ethylene glycol. The Transmission Electron Microscopy and Inductively Coupled Plasma Optical Emission Spectroscopy were employed to characterize the synthesized PtRuCo/GR catalysts. The electrocatalytic activity of the synthesized catalysts towards the oxidation of methanol was investigated by means of cyclic voltammetry and chronoamperometry. It was found that the PtRuCo/GR catalysts with the Pt:Ru:Co molar ratios equal to 1:2:2, 1:1.7:5.6 and 3.5:1:23 were prepared. The PtRuCo/GR catalyst with the Pt:Ru:Co molar ratio equal to 3.5:1:23 has a higher electrocatalytic activity towards the oxidation of methanol in acidic medium as compared with that of other synthesized catalysts.

In this study, cobalt-nickel (Co-Ni), cobalt-iron (Co-Fe), cobalt-iron-manganese (Co-Fe-Mn), cobalt-iron-molybdenum (Co-Fe-Mo), and cobalt-zinc (Co-Zn) coatings were studied as catalysts towards the evolution of hydrogen (HER) and oxygen (OER). The binary and ternary Co coatings were deposited on a copper surface using the electroless metal plating technique and morpholine borane (MB) as a reducing agent. The as-deposited Co-Ni, Co-Fe, Co-Fe-Mn, Co-Fe-Mo, and Co-Zn coatings produce compact and crack-free layers with typical globular morphology. It was found that the Co-Fe-Mo coating gives the lowest overpotential of 128.0 mV for the HER and the lowest overpotential of 455 mV for the OER to achieve a current density of 10 mA cm−2. The HER and OER current density values increase 1.4–2.0 times with an increase in temperature from 25 °C to 55 °C using the prepared 3D binary or ternary cobalt coatings for HER and OER. The highest mass electrocatalytic activity of 1.55 mA µg−1 for HER and 2.72 mA µg−1 for OER was achieved on the Co-Fe coating with a metal loading of 28.11 µg cm−2 at 25 °C.

Graphene supported PtCo catalysts with the Pt:Co molar ratios equal to 1:1, 1:7 and 1:44 were fabricated by means of the rapid microwave heating method. A shape and size of catalyst particles were characterized using transmission electron microscopy. The structure and composition of the synthesized catalysts were examined by X-ray diffraction and inductively coupled plasma optical emission spectroscopy. The electrocatalytic activity of the synthesized catalysts toward the oxidation of ethanol in an alkaline medium was investigated by means of cyclic voltammetry and chrono-techniques. It has been determined that the graphene supported PtCo catalyst with a Pt:Co molar ratio equal to 1:7 exhibits highest electrocatalytic activity for the oxidation reaction of ethanol as compared with those at the graphene supported bare Co and PtCo catalysts with Pt:Co molar ratios equal to 1:1 and 1:44.