Suppressing the hydrogen bonding interaction with *OOH toward efficient H2O2 electrosynthesis via remote electronic tuning of Co-N4

Abstract

The non-covalent interaction that appears along with electronic tuning is often overlooked in interpreting the oxygen reduction reaction (ORR) dynamics, resulting in a limited understanding of the governing principles. Herein, through intricately engineering pedant substituents on porphyrins backbones, Co-N moieties featuring varied electronic configurations served as an exemplary model to elucidate the role of hydrogen bonding interaction appears along with electronic tuning in determining 2e ORR performance. Co-TEPP with an electron-deficient Co-N moiety emerges as a standout performer for O-to-HO conversion. Upon covalently linking the Co-TEPP monomer on rGO to form robust organic polymer structures (Co-TEPP-COP/rGO), superior HO selectivity (> 95 %), remarkable HO production rate (∼18.8 mol g h), and excellent performance durability are identified. Such optimized HO electrosynthesis could be attributed to the suppressed hydrogen bonding interaction between *OOH and electron-deficient Co-N moiety, which consequently weakens *OOH binding strength to favor HO electrosynthesis.