TiO2 nanotube supported PdNi catalyst for methanol electro-oxidation

Abstract A novel PdNi/TiO 2 nanotube electrocatalyst was successfully prepared by the surface reductive deposition method using the PdCl 2 and NiSO 4 as precursors and porous TiO 2 nanotube as carrier. The structural and electrochemical properties of the PdNi/TiO 2 nanotube catalyst were characterized by XRD, TEM and electrochemical analysis. The experiments results showed that TiO 2 nanotube had large surface area and porous structure that is preferable to the dispersion of nanosized PdNi on the surface of the TiO 2 nanotube support. The cyclic voltammograms in 1 mol L − 1 CH 3 OH and 1 mol L − 1 H 2 SO 4 showed that the large oxidation peak potential was about 0.94 V on the positive irreversible scan and another acute peak of methanol oxidation was 0.85 V on the reverse scan that was much bigger than that of the standard PtRu/C catalyst, the PdNi/TiO 2 nanotube electrocatalyst had higher catalytic activity for methanol electro-oxidation than standard PtRu/C catalyst. The methanol oxidation mechanism of the PdNi/TiO 2 nanotube catalyst was mainly depended on the photocatalytic mechanism of TiO 2 and the synergistic effect between PdNi bimetal and the carrier TiO 2 nanotube. The PdNi/TiO 2 nanotube catalyst should be a promising candidate for direct methanol fuel cell.