Fused Hybrid Linkers for Metal–Organic Frameworks-Derived Bifunctional Oxygen Electrocatalysts

Abstract

Preparation of electrocatalysts often relies on the use of multiple starting materials-inorganic salts or organometallic precursors, nanostructured carbon supports, organic additives, dopants and carbonization under modifying atmospheres (e.g. NH 3 or H 2)-with the examples of electrocatalysts arising from a single precursor being much less common. Herein, we have surveyed a series of heterobivalent scaffolds to identify an iron/benzimidazole-based metal-organic framework as a uniform starting material. By merging the catechol and imidazole units together, we get direct entry into a highly efficient bifunctional oxygen electrocatalyst, which alleviates the need for additional dopants and modifying conditions (ORR: E on = 1.01 V, E 1/2 = 0.87 V vs. RHE in 0.1 M KOH; OER: 1.60 V @10 mA cm-2 in 0.1 M KOH; ∆E = 0.73 V). We demonstrate that by fine-tuning the chemical nature of an organic linker, one is able modulate the electrochemical properties of a single precursor-derived electrocatalyst material. File list (2) download file view on ChemRxiv Ping et al_v2.pdf (1.09 MiB) download file view on ChemRxiv Ping_et_al_SI_v2.pdf (2.83 MiB)