Effect of the Composition and Structure of Pt(Cu)/C Electrocatalysts on Their Stability under Different Stress Test Conditions

Stability is one of the most important characteristics of electrocatalysts used in low-temperature fuel cells with a proton exchange membrane. The corrosion-morphological stability of supported electrocatalysts containing platinum and platinum-copper nanoparticles with similar to 20 wt % Pt was evaluated under the conditions of voltammetry stress testing corresponding to different degradation mechanisms. The effect of the difference in the architecture of Pt-Cu nanoparticles on the stability of catalysts and changes in their composition as a result of stress tests were studied. At close values of the electrochemically active surface area (ECAS), the carbon-supported bimetallic catalysts demonstrated significantly higher stability compared to the commercial Pt/C catalysts. The Pt(Cu)/C catalyst obtained by sequential deposition of copper and platinum showed the highest resistance to the degradation and selective dissolution of copper during the testing.