Boosting acidic hydrogen peroxide electrosynthesis on 2D metal-organic framework nanosheets based on cobalt porphyrins

The 2-electron electrocatalytic oxygen reduction reaction (2e-- ORR) to hydrogen peroxide (H2O2) 2 O 2 ) represents a promising strategy to resolve the high energy consumption and increasing environmental concerns inherent in the traditional anthraquinone process. The acidic 2e-- ORR has emerged as an exciting alternative for industrial- level H2O2 2 O 2 production, whereas is hampered by the inferior H2O2 2 O 2 selectivity due to the uncontrollable proton- coupled electron transfer processes in an acidic environment. Herein, an ultrathin 2D metal-organic frameworks (MOFs) nanosheet based on cobalt tetra(4-carboxyphenyl) porphine (Co-TCPP NSs) is designed to promote H2O2 2 O 2 selectivity up to 96.5 %, accompanied with a remarkable H2O2 2 O 2 generation rate of 4677.42 mg center dot L-- 1 center dot h- 1 . Of note, the Co-TCPP NSs also demonstrate its potential for the electro-Fenton process with a cumulative H2O2 2 O 2 concentration of 1.21 wt%, highlighting its practical potential in portable H2O2 2 O 2 generation electrochemical devices for distributed applications. Our findings demonstrated that the efficient H2O2 2 O 2 electrosynthesis could be attributed to the attenuated *OOH adsorption over Co-N4 4 moiety on the Co-TCPP NSs, which consequently suppresses its further reduction to form H2O. 2 O. This work highlights the potential of 2D MOF architecture for the 2e-- ORR and provides an atomic-level insight into the enhanced H2O2 2 O 2 selectivity.