Electrochemical and surface characteristics of carbon-supported PtSn electrocatalysts for ethanol electro-oxidation: possible application for inkjet ink formulations

H Y Hsu and B J Tongol

Abstract

Pt and Pt_xSn_y catalysts with different atomic ratios (90:10, 80:20, 70:30, 60:40 and 50:50) supported on carbon support (Vulcan XC-72) were prepared using the modified polyol method. The composition, particle size and structure of these catalysts were characterized by energy dispersive x-ray spectroscopy (EDX) and x-ray diffraction (XRD). XRD data revealed that the estimated particle sizes of all synthesized catalysts were approximately 2.0–3.0 nm. Cyclic voltammetric data showed that Pt₈₀Sn₂₀ exhibited the highest catalytic activity toward ethanol oxidation compared to other ratios in terms of area-normalized current densities. Chronoamperometry (CA) data confirmed that Pt₇₀Sn₃₀was the most stable among the prepared catalysts with long-term poisoning rate of 4.25 × 10^–3 (% s⁻¹), which was four times lower than Pt (1.70 × 10⁻²). The catalyst with the optimum performance was used as the ink pigment of the inkjet ink formulations