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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.

Direct hydrazine fuel cells (DHFCs) are one type of direct liquid fuel cells (DLFCs), where hydrazine is used as a fuel. DHFCs can be operated using a non-precious metal catalyst, which potentially contributes to cost reduction of the hydrazine fuel cell technology. Despite the tremendous progress made in the development of an active catalyst for DHFCs, however, available perfect catalyst able to meet the power output requirements for commercial fuel cell vehicles is still an issue. In this chapter, we summarize the recent advances in the development of catalysts for direct hydrazine fuel cells (DHFCs). The challenges and perspectives in this field are also discussed.

The graphene (GR) supported platinum–tungsten (PtW) catalysts with Pt:W molar ratios, equal to 1.6:1, 2.3:1 and 7.1:1, were prepared by a rapid microwave-assisted heating method. The activity of the catalysts was investigated for the electro-oxidation of methanol in an alkaline medium by means of cyclic voltammetry (CV) and chronoamperometry (CA). It has been determined that the rate of methanol oxidation depends on the Pt:W molar ratio in the PtW/GR catalysts. From the CV measurements it follows that the highest current density values, specific and mass activities are obtained for the PtW/GR catalyst with the Pt:W molar ratio equal to 1.6:1. Similarly, the chronoamperometry measurements point to the best performance of the PtW/GR catalyst with the same Pt:W molar ratio. Moreover, in all cases the synthesized PtW/GR catalysts, regardless of different Pt:W molar ratio, show an enhanced electrocatalytic activity towards the direct electro-oxidation of methanol when compared with that for the bare Pt/GR and W/GR catalysts.