Pocket-shaped air-breathing electrodes used for in-situ synthesis of hydrogen peroxide and application

A novel pocket-shaped air-breathing electrode (PSABE) is prepared using carbon material (CM), polytetrafluorethylene (PTFE), pulp and filler. Additionally, an in-situ electro-synthesis of H 2 O 2 is constructed using the PSABE and the carbon felt. The results show that under current density of 50 mA/cm 2 and solution pH of 3, compared with classical gas diffusion electrode and micropore-adjusted gas diffusion electrode, the PSABE's H 2 O 2 yield is the highest and 110.1 mg/(L.cm 2 ) in 90 min, and its oxygen diffusion coefficient is also the highest and 1.68 × 10 −5 m 2 /s. When the optimal mass ratio of PTFE:filler in the electrode wall:filler in the electrode pocket:CM is 1.5:3:3:1, the PSABE's H 2 O 2 yield further climbs to 112.0 mg/(L.cm 2 ). A series of detections show that when filler in the electrode wall increases, the PSABE's pore structure is more abundant, active sites are more and oxygen diffusion capability becomes better. Similarly, when filler in the electrode pocket increases, air mobility inside and outside the cavity goes easier and the PSABE oxygen diffusion capability improves, too. Additionally, when current density varies from 20 to 70 mA/cm 2 , H 2 O 2 yield for 70 mA/cm 2 can attain to 143.4 mg/(L.cm 2 ) while current efficiency and energy consumption for 20 mA/cm 2 is 84.9% and 8.4 KWh/kg, respectively. Moreover, results of H 2 O 2 yield, disinfection and wastewater treatment show that the prepared PSABE is effective and feasible.