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Missing-linker metal-organic frameworks for oxygen evolution reaction.

ABSTRACT: Metal-organic frameworks (MOFs) have been recognized as compelling platforms for the development of miscellaneous applications because of their structural diversity and functional tunability. Here, we propose that the electrocatalytic properties could be well modified by incorporating missing linkers into the MOF. Theoretical calculations suggest the electronic structure of MOFs can be tuned by introducing missing linkers, which improves oxygen evolution reaction (OER) performance of the MOF. Inspired by these aspects, we introduced various missing linkers into a layered-pillared MOF Co2(OH)2(C8H4O4) (termed as CoBDC) to prepare missing-linker MOFs. Transmission electron microscope and synchrotron X-ray measurements confirmed that the missing linkers in the MOF could be introduced and well controlled by our strategy. The self-supported MOF nanoarrays with missing linkers of carboxyferrocene exhibit excellent OER performance with ultralow overpotential of 241?mV at 100?mA?cm-2. This work opens a new prospect to develop efficient MOF-based electrocatalysts by introducing missing linkers.

SUBMITTER: Xue Z

PROVIDER: S-EPMC6834668 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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