Platinum-zeolite hybrid catalyst for the electrooxidation of formic acid

Formic acid oxidation reaction (FAOR) was studied using different platinum-zeolites hybrid catalysts. The catalysts were prepared by addition of two forms the ZSM-5 zeolite (ZSM-5-H+ and ZSM-5-NH4+) to an ink containing Vulcan carbon support Pt nanoparticles (NPs). TEM images demonstrate a proper mixture components in good dispersion NPs mainly over carbon. Both zeolites (ZSM-5-NH4+ ZSM-5-H+) are stable under electrochemical conditions for FAOR, but ZSM-5-NH4+ undergoes fast conversion into ZSM-5-H+ due exchange between compensator cation protons solution. A significant enhancement on catalytic activity found both catalysts, being more time. In particular, 7 10 times larger current densities than 9 wt% Pt/C achieved (7 Pt/18.5 ZSM-5-NH4+/C) ZSM-5-H+/C) chronoamperometry, respectively. results demonstrated beneficial synergetic effect order improve NPs. within electrocatalyst did not provoke any relevant modification type features displayed cyclic voltammetry, provoked peak density associated with CO stripping. We propose that mechanism this improvement lies efficient distribution thanks presence preconcentration reactant (HCOOH) microporosity occurring Moreover, local pH modifications NH4+/H+ could have some impact kinetics FAOR direct via.