Stable H2O2 electrosynthesis at industrially-relevant currents by a membrane-based electrode with high oxygen accessibility

Electrosynthesis of hydrogen peroxide (H 2 O 2 ) presents a sustainable alternative to the anthraquinone process, while the transition to applying this process at industrial-relevant currents remains a significant challenge. Most studies tried to solve it by catalysts modulations, whereas we found that the accessibility to the gaseous O 2 , might be the crux of this matter. Herein, we developed a series of membrane-based gas diffusion electrodes (Mem-GDEs) with varied O 2 accessibility. Their endurable currents were found to be well correlated with the O 2 mass transferability. By constructing high O 2 -accessible triphasic interfaces, Mem-GDE achieved a recorded current density , 1.4 A cm −2 , with the current efficiency higher than 80.6 %. It was also verified for the first time that the insufficient O 2 triggered a severe flooding problem and thus further deteriorate the O 2 mass transfer. This study highlights the importance of O 2 accessibility and provides new insights into triphasic interfaces construction for realizing industrial-used H 2 O 2 -generated electrodes.