High electrocatalytic activity and stability of Pt/TNT-RuO2

In recent years, the high cost and limited stability of platinum-based catalysts in proton exchange membrane fuel cells (PEMFCs) have emerged as critical challenges hindering their widespread commercialization. TiO₂ nanotubes (TNT), characterized by its one-dimensional hollow structure, high specific surface area, and chemical inertness, effectively anchors platinum nanoparticles and inhibits their migration and agglomeration. The incorporation of RuO₂ not only enhances the conductivity of the support but also promotes electronic synergy with platinum, thereby significantly improving both catalytic activity and stability. TNT-RuO₂ was synthesized by integrating alkaline hydrothermal synthesis with the wet chemical method, thereby optimizing the dispersion of platinum and forming a strong metal-support interaction (SMSI). The synergistic oxygen reduction catalysis and high conductivity of RuO₂ can compensate for the low catalytic activity of the catalyst caused by the insufficient conductivity of TNT. This composite carrier system not only mitigates carbon carrier oxidation and degradation through the corrosion resistance of TiO₂ but also inhibits platinum Ostwald ripening by leveraging the stable oxidation state of RuO₂. Research has confirmed that the electrochemical active surface area (ECSA) of Pt/TNT-RuO₂ is 60.5 m²·g⁻¹, compared to 44.7 m²·g⁻¹ for Pt/C. After 10,000 cycles of accelerated stress testing, the EASA of the composite carrier catalyst decreased by only 33.9%, significantly lower than the 40.3% decay rate observed for Pt/C. This innovation offers a promising new approach for developing high-stability and cost-effective PEMFC catalysts.