Facile template-assisted synthesis of PtBiTe nanoplates for CO-free methanol oxidation in alkaline electrolytes

Abstract

It is important to develop efficient catalysts for improving performance and reducing the cost of direct methanol fuel cells, very promising power sources for portable devices and vehicles. Composition optimization and shape control are two effective strategies to develop high-performance catalysts. Inspired by the excellent performance of PtBi-type catalysts in inhibiting CO-poisoning and the outstanding electrocatalytic performance of two-dimensional Pt-based alloy nanoplates, the synthesis of PtBiTe hexagonal nanoplates using Bi₂Te₃ hexagonal nanoplates as templates is proposed here. Both the Bi₂Te₃ nanoplates and the PtBiTe nanoplates have a hexagonal plate-like shape. The PtBiTe nanoplate catalyst displays outstanding specific activity and mass activity, and superior stability for the methanol oxidation reaction in alkaline electrolytes compared to the commercial Pt/C catalyst and the PtTe nanoplate catalyst. The results of the in situ Fourier transform infrared spectroscopy measurements and the theoretical calculations based on the density functional theory support that methanol oxidation follows the CO-free pathway on the PtBiTe NPs, which effectively prevents the catalyst from being poisoned by CO.