Highly Stable and Methanol Tolerant RuTe2/C Electrocatalysts in Alkaline Media

Abstract

The carbon supported ruthenium tellurium (RuTe2/C) nanoparticles were synthesized through a simple microwave polyol method and heat treatment at 350℃. Effects of Ru/Te molar ratio on the crystal structure, surface morphology, microstructure, electrocatalytic activity and stability, as well as methanol tolerance in both acidic and alkaline solutions were systematically investigated. The orthorhombic RuTe2 and hexagonal Ru were formed. The catalyst nanoparticles were uniformly dispersed on carbon support and the average particle size ranged 5.0~8.6 nm. The best activities toward oxygen reduction reaction (ORR) were achieved with the RuTe2/C catalyst prepared at Ru/Te=1:1 in both acidic and alkaline media. The onset (Eonset ) and half-wave potentials (E1/2 ) were 0.88 and 0.60 V in 0.1 mol/L HClO4, respectively, while 0.98 and 0.72 V in 0.1 mol/L KOH, respectively. The E1/2 values decreased by 5 mV after 1000 cycles in both acidic and alkaline electrolytes, while 20 mV and 7 mV in both acidic and alkaline electrolytes containing 2 mol/L methanol, respectively, suggesting the excellent stability and methanol tolerance.