This paper describes the activity of PdCo₃O₄/C obtained by wet impregnation towards the oxygen reduction reaction (ORR). For this purpose, the Co₃O₄/C substrate was synthesized using the microwave irradiation heating method with further annealing of the substrate at 400 °C for 3 h (Co₃O₄/C-T). Then, the initial Co₃O₄/C substrate was impregnated with palladium chloride (Pd-Cl₂-Co₃O₄/C), and then part of the obtained Pd-Cl₂-Co₃O₄/C catalyst was annealed at 400 °C for 3 h (PdOCo₃O₄/C). The electrocatalytic activity of the prepared catalysts was investigated for the oxygen reduction reaction in alkaline media and compared with the commercial Pt/C (Tanaka wt. 46.6% Pt) catalyst. It was found that the annealed PdOCo₃O₄/C catalyst showed the largest ORR current density value of −11.27 mA cm⁻² compared with Pd-Cl₂-Co₃O₄/C (−7.39 mA cm⁻²) and commercial Pt/C (−5.25 mA cm⁻²).

In this study, ternary NiFeP coatings were fabricated on a copper substrate using a simple, fast, and cost-effective electroless deposition method. The coatings were named Ni₈₅Fe₄P₁₂, Ni₈₀Fe₈P₁₂, and Ni₇₅Fe₁₂P₁₂, indicating 4, 8, and 12 at % of Fe, respectively. The surface morphology and composition of the coatings were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The activity of the prepared coatings was evaluated using the water-splitting reaction to determine the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a 1 M KOH electrolyte solution. Electrochemical measurements were carried out in a temperature range from 25 °C to 55 °C. The HER and OER current density values increased by up to 2.58 and 2.13 times, respectively, with temperature increase compared to the result at 25 °C. All three coatings demonstrated activity in both reactions. Ni₈₅Fe₄P₁₂ exhibited the highest catalytic efficiency in the HER, with the overpotential of 340 mV at 10 mAcm⁻² and a Tafel slope of 61 mVdec⁻¹. In the OER, the efficiency of the NiFeP catalysts correlated with their Fe content. The overpotential was 412 mV for Ni₈₀Fe₈P₁₂ and 432 mV for Ni₇₅Fe₁₂P₁₂ at 10 mAcm⁻² with Tafel slopes of 96 and 91 mVdec⁻¹, respectively. This study underscores the critical influence of Fe content on the catalytic efficiency of NiFeP coatings, with reduced Fe content enhancing HER and increased Fe content benefits OER.

In this study, one-pot microwave-assisted synthesis was used to fabricate the graphene (GR)-supported PtCoM catalysts where M = Mn, Ru, and Mo. The catalysts with the molar ratios of metals Pt:Co:Mn, Pt:Co:Ru, and Pt:Co:Mo equal to 1:3:1, 1:2:2, and 7:2:1, respectively, were prepared. Catalysts were characterized using Transmission Electron Microscopy (TEM). The electrocatalytic activity of the GR-supported PtCoMn, PtCoRu, and PtCoMo catalysts was evaluated toward methanol oxidation in an alkaline medium employing cyclic voltammetry and chrono-techniques. The most efficient electrochemical characteristics demonstrated the PtCoMn/GR catalyst with a current density value of 144.5 mA cm⁻², which was up to 4.8 times higher than that at the PtCoRu(1:2:2)/GR, PtCoMo(7:2:1)/GR, and bare Pt/GR catalysts.

This paper describes the investigation of electrocatalytic activity of the AuCeO₂/C catalyst, prepared using the microwave irradiation method, towards the oxidation of sodium borohydride and oxygen reduction reactions in an alkaline medium. It was found that the obtained AuCeO₂/C catalyst with Au loading and electrochemically active surface area of Au nanoparticles (AuNPs) equal to 71 µg cm⁻² and 0.05 cm², respectively, showed an enhanced electrocatalytic activity towards investigated reactions, compared with the Au/C catalyst with an Au loading and electrochemically active surface area of AuNPs equal to 78 µg cm⁻² and 0.19 cm², respectively. The AuCeO₂/C catalyst demonstrated ca. 4.5 times higher current density values for the oxidation of sodium borohydride compared with those of the bare Au/C catalyst. Moreover, the onset potential of the oxygen reduction reaction (0.96 V) on the AuCeO₂/C catalyst was similar to the commercial Pt/C (0.98 V).

The production of high-purity hydrogen from chemical hydrogen storage materials such as sodium borohydride (NaBH₄) has been identified as a particularly promising candidate due to its high hydrogen storage capacity and environmentally benign hydrolysis products. The incorporation of tungsten (W), thereby developing W-promoted NiMo catalytic systems, results in the enhance activity toward NaBH₄ hydrolysis, thereby developing ternary NiMoW catalytic systems. The synthesis of NiMoW-coated copper catalysts (NiMoW/Cu) containing 3–11 wt.% of W was accomplished using a cost-effective and efficient electroless deposition method from citrate-based plating baths containing Ni²⁺, Mo⁶⁺, and W⁶⁺ ions. Morpholine borane was utilized as the reducing agent in this process. The catalytic activity of the prepared coatings toward alkaline NaBH₄ hydrolysis increased as the tungsten content decreased within the investigated range of 3–11 wt.%. The highest hydrogen generation rate, reaching 9.87 L min⁻¹ gcat⁻¹, was achieved using the NiMoW/Cu catalyst containing 3 wt.% of W at 343 K. The corresponding apparent activation energy was calculated to be 52 kJ mol⁻¹. In addition, the catalyst demonstrated notable 89.1% stability, maintaining a high degree of catalytic activity after undergoing five successive hydrolysis cycles. The enhanced catalytic performance was attributed to synergistic interactions between Ni, Mo, and W and to the favorable surface morphology of the multicomponent coating, which promoted the hydrogen generation reaction.