Mesoporous titanium nitride supported Pt nanoparticles as high performance catalysts for methanol electrooxidation

Abstract

Mesoporous titanium nitride (TiN) with high surface area and good electrical conductivity was prepared by a novel solid–solid phase separation method from a Zn containing titanium oxide, Zn₂TiO₄. The PXRD shows single phase rocksalt structure of TiN with a domain size of 25 nm. The conductivity of mesoporous TiN at 35 bar is 395 S cm⁻¹. The Pt/TiN catalyst exhibits more negative onset potential for methanol electrooxidation (0.15 V) than Pt/C (0.22 V), showing a higher intrinsic electrocatalytic activity, while its peak current density (228 mA mg⁻¹ Pt) is ∼1.5 times higher than that of Pt/C (148 mA mg⁻¹ Pt). The Pt/TiN catalyst also demonstrates excellent long-term stability. This work provides an efficient method to prepare mesoporous nitrides as a promising support towards oxidation of small organic molecules in fuel cells.