Hydrothermal synthesis of PtRu on CNT/SnO2 composite as anode catalyst for methanol oxidation fuel cell

An electrocatalyst support comprising of carbon nanotube and tin oxide (CNT/SnO2) was prepared by an ethylene glycol mediated synthesis procedure and proposed as an improved catalyst support for direct methanol fuel cell. CNTs are covered by the porous SnO2 layer which is homogeneously distributed over CNT surface. PtRu alloy nanoparticles were deposited over this composite material by a hydrothermal synthesis method. The CNT/SnO2 composite and its supported PtRu catalyst (PtRu/SnO2/CNT) were characterized by X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy. The electrocatalytic activity of PtRu/SnO2/CNT catalyst for methanol oxidation has been studied by cyclic voltammetry, impedance spectroscopy and chronoamperometry. The results were compared with Pt/SnO2/CNT and PtRu/CNT catalysts synthesized by the same procedure. PtRu/SnO2/CNT catalyst shows an electrochemically active surface area of 81.84 m2 gPt−1 and a mass activity of 890 mA mgPt−1. The presence of SnO2 layer over CNT can further improve the electrocatalytic activity of PtRu alloy nanoparticles for methanol oxidation.

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► CNTs are homogeneously covered by the porous SnO2 layer which enhanced the electronic property of the catalyst support as well as the catalyst and fuel interaction.
► PtRu/SnO2/CNT catalyst shows an electrochemically active surface area of 81.84 m2 gPt−1 and a mass activity of 890 mA mgPt−1.
► Hydrothermal synthesis offers small particle size as well as well dispersion of the catalyst nanoparticles.
► Addition of SnO2 with PtRu provides an additional route for OHads formation and hence accelerates methanol oxidation.