Research group of Dr. Shu-Hong Yu from University of Science and Technology of China made progress on methanol oxidation electrocatalyst and published their work on J. Am. Chem. Soc..
This paper reported the synthesis of a quaternary PtPdRuTe nanotube (NT) for methanol oxidation reaction (MOR) with controlled composition by galvanic replacement reaction. The relationship between morphology and composition of the NTs was established. As quaternary Pt-based catalysts, each component of the NTs fulfills an important role in the electrocatalysis, improving the heteroatomic interactions. The unreacted Te atoms support the NT skeleton and minimize the loading of other three precious metals. The Pt atomic ratio of the best catalysts for MOR is only 17%. The Pt atoms served as the active sites for MOR to dehydrogenated methanol forming Pt-CO, while the more oxophilic Ru sites are facilitated to the adsorption of oxygen species forming Ru-OH at lower potential, preferentially oxidize COad to produce CO2 and refreshing new active sites (bifunctional mechanism). The introduction of a few Pd atoms into the NT catalysts improved the surface reactivity during the long-term stability tests due to its higher reduction potential and modified electronic structure of Pt. In comparison with the ternary PtRuTe catalysts, quaternary system is also expected to display not only great synergic effect of each component to further boost the catalytic activities, but also new properties and stability of the catalysts. Pd is known as stable element for their stabilization effect to decrease Pt oxidation and corrosion by up-shifting the dissolution potential of Pt. The resultant quaternary component catalysts show enhanced catalytic activity and durability toward the MOR.