Oxygen Vacancy and Interface Effect Adjusted Hollow Dodecahedrons for Efficient Oxygen Evolution Reaction

Molecules. 2023 Jul 25;28(15):5620. doi: 10.3390/molecules28155620.

Abstract

Metal-organic frameworks (MOFs) with special morphologies provide the geometric morphology and composition basis for the construction of platforms with excellent catalytic activity. In this work, cobalt-cerium composite oxide hollow dodecahedrons (Co/Cex-COHDs) with controllable morphology and tunable composition are successfully prepared via a high-temperature pyrolysis strategy using Co/Ce-MOFs as self-sacrificial templates. The construction of the hollow structure can expose a larger surface area to provide abundant active sites and pores to facilitate the diffusion of substances. The formation and optimization of phase interface between Co3O4 and CeO2 regulate the electronic structure of the catalytic site and form a fast channel favorable to electron transport, thereby enhancing the electrocatalytic oxygen evolution activity. Based on the above advantages, the optimized Co/Ce0.2-COHDs obtained an enhanced oxygen evolution reaction (OER) performance.

Keywords: cobalt–cerium composite oxide; hollow dodecahedrons; metal–organic frameworks; oxygen evolution reaction; phase interface.