Enlarging the Ni–O Bond Polarizability in a Phosphorene-Hosted Metal–Organic Framework for Boosted Water Oxidation Electrocatalysis

Abstract

The emerging lattice-oxygen oxidation mechanism (LOM) presents attractive opportunities for breaking the scaling relationship to boost oxygen evolution reaction (OER) with the direct O Lattice −*O interaction. However, currently the LOM-triggering rationales are still debated, and a streamlined physicochemical paradigm is extremely desirable for the design of LOM-defined OER catalysts. Herein, a Ni metal−organic framework/black phosphorene (NiMOF/BP) heterostructure is theoretically profiled and constructed as a catalytic platform for the LOM-derived OER studies. It is found that the p-type BP host can enlarge the Ni−O bond polarizability of NiMOF through the Ni−O bond stretching and Ni valence declining synergically. Such an enlarged bond polarizability will in principle alleviate the lattice oxygen confinement to benefit the LOM pathway and OER performance. As a result, the optimized NiMOF/BP catalyst exhibits promising OER performance with a low overpotential of 260 mV at 10 mA cm −2 and longterm stability in 1 M KOH electrolyte. Both experiment and calculation results suggest the activated LOM pathway with a more balanced step barrier in the NiMOF/BP OER catalyst. This research puts forward Ni−O bond polarizability as the criterion to design LOM-scaled electrocatalysts for water oxidation.

A dual-functional metalloporphyrin-fluorenone covalent organic framework for solar hydrogen and oxygen production

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Research progress on layered metal oxide electrocatalysts for an efficient oxygen evolution reaction

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In Situ Reconstructed Layered Double Hydroxides via MOF Engineering and Ru Doping for Decoupled Acidic Water Oxidation Enhancement

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