Pulsed Electrolysis of Boron-Doped Carbon Dramatically Improves Impurity Tolerance and Longevity of H2O2 Production

Electrocatalytic water treatment has emerged in the limelight of scientific interest, yet its long-term viability remains largely in the dark. Herein, we present for the first time a comprehensive framework on how to optimize pulsed electrolysis to bolster catalyst impurity tolerance and overall longevity. By examining real wastewater constituents and assessing different catalyst designs, we deconvolute the complexities associated with key pulsing parameters to formulate optimal sequences that maximize operational lifetime. We showcase our approach for cathodic H2O2 electrosynthesis, selected for its widespread importance to wastewater treatment. Our results unveil superior performance for a boron-doped carbon catalyst over state-of-theart oxidized carbon, with high selectivity (>75%) and near complete recoveries in overpotentials even in the presence of highly detrimental Ni2+ and Zn(2+ )impurities. We then adapt these fine-tuned settings, obtained under a three-electrode arrangement, for practical two-electrode operation using a novel strategy that conserves the desired electrochemical potentials at the catalytic interface. Even under various impurity concentrations, our pulses substantially improve long-term H2O2 production to 287 h and 35 times that attainable via conventional electrolysis. Our findings underscore the versatility of pulsed electrolysis necessary for developing more practical water treatment technologies.

Automated summary

Electrocatalytic water treatment using pulsed electrolysis is explored to enhance catalyst impurity tolerance and longevity. By analyzing real wastewater constituents and evaluating various catalyst designs, optimal pulsing sequences are formulated to maximize operational lifetime. Superior performance is achieved with a boron-doped carbon catalyst, showing high selectivity (>75%) and near complete recoveries even in the presence of detrimental impurities. A novel strategy is developed to adapt the fine-tuned settings for practical two-electrode operation, resulting in significantly improved long-term hydrogen peroxide production. The findings highlight the versatility of pulsed electrolysis for developing more practical water treatment technologies.