Methanol Oxidation on Pt/CNT Electrocatalysts Promoted with TiO2

Electrocatalytic materials are a major challenge for Direct Methanol Fuel Cells (DMFC) commercialization. To improve the properties of supported Pt electrocatalysts, various metal oxides are used to enhance the methanol oxidation performance [1‑3]. Currently, titanium oxide is widely studied as electrocatalytic promoter due to its low cost and stability in acid media [1‑3]. 

In this research, Pt-xTiO₂/CNT electrocatalysts with various titanium oxide loadings (x= 5, 10 and 20 wt%) were prepared. In first instance, the titanium oxide was incorporated to CNT by a sonochemical method to obtain the system TiO₂/CNT. Then, 10 wt% of Pt nanoparticles were incorporated to TiO₂/CNT by sonochemical conditions using NaBH₄ as a reducing agent.

The chemical composition of the systems was determinated by ICP analysis. The electrocatalysts structure was characterized by XRD diffraction and HRTEM. The nitrogen adsorption was performed to determinate the specific surface area by the BET method. The electrochemical study was performed by cyclic voltammetry in a three-electrode half-cell at room temperature.

Pt-xTiO₂/CNT electrocatalysts were successfully synthesized by a short time synthesis method. The results of the cyclic voltammetry test for the methanol oxidation suggest that the incorporation of TiO₂ improves the electrocatalytic activity of the synthesized materials, in comparing to the system Pt/CNT.

The authors acknowledge CONACyT project 174689 and PAPIIT IN104714.

References

[1]W. Xiuyu, Z. Jingchang, Z. Hong, Chin. J. Catal., 32 (2011), 74-79.

[2]W. Wang, H. Wang, J. Key, V. Link, et al., Ionics, 19 (2013), 529‑534

[3] P. Kolla, A. Smirnova, Int. J. Hydrogen Energy, (2013), 1‑8.