Coupling homogeneous and heterogeneous catalysis for enhancement of HCOOH electrooxidation via the dehydrogenation pathway

The homogeneous/heterogeneous catalyst combination of VO²⁺ in anolyte with Pd/C at the anode is first introduced in a formic acid fuel cell to enhance HCOOH electrooxidation. The VO²⁺/Pd catalyst combination establishes a stepwise reaction pathway involving HCOOH dehydrogenation to form V²⁺ from VO²⁺ reduction and subsequent V²⁺ electrooxidation to regain VO²⁺. The fuel cell with the VO²⁺/Pd combination presents a peak power density of 341.3 mW cm⁻² and stable power density higher than 30 mW cm⁻².