Hydrogen peroxide electrogeneration in gas diffusion electrode nanostructured with Ta2O5

Highly efficient H 2 O 2 electrogeneration is required in the Advanced Oxidation Process for organic wastewater treatment. However, the development of more efficient catalytic particles used in gas diffusion electrodes (GDEs) to enable the oxygen reduction reaction through two-electron transfer is still of great importance. The performance of the Ta 2 O 5 nanoparticles on carbon black in catalyzing the ORR was evaluated using rotating ring-disk electrode. The current efficiency for H 2 O 2 electrogeneration on Ta 2 O 5 /C catalyst is 83.2% whereas carbon black exhibits 65.3%. GDEs were constructed using carbon black either unmodified or modified with Ta 2 O 5 nanoparticles. The modified GDE produces 27.9 mg L -1 of H 2 O 2 , while the unmodified GDE generates 19.1 mg L -1 of H 2 O 2 . Furthermore, the energy consumption for the H 2 O 2 electrogeneration is lower in modified than in unmodified GDE (15.0 kW h vs. 18.8 kW h). The high performance of the GDE (Ta 2 O 5 /C) renders it a viable alternative cathode in the electrochemical treatment of wastewaters.