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Earth-abundant oxygen evolution catalysts (OECs) with extended stability in acid can be constructed by embedding active sites within an acid-stable metal-oxide framework. Here, we report stable NiPbO_xfilms that are able to perform oxygen evolution reaction (OER) catalysis for extended periods of operation (>20 h) in acidic solutions of pH 2.5; conversely, native NiO_xcatalyst films dissolve immediately. In situ X-ray absorption spectroscopy and ex situ X-ray photoelectron spectroscopy reveal that PbO₂is unperturbed after addition of Ni and/or Fe into the lattice, which serves as an acid-stable, conductive framework for embedded OER active centers. The ability to perform OER in acid allows the mechanism of Fe doping on Ni catalysts to be further probed. Catalyst activity with Fe doping of oxidic Ni OEC under acid conditions, as compared to neutral or basic conditions, supports the contention that role of Fe³⁺in enhancing catalytic activity in Ni oxide catalysts arises from its Lewis acid properties.

Metal–organic frameworks (MOFs) have been extensively used for single‐site catalysis and light harvesting, but their application in multicomponent photocatalysis is unexplored. We report here the successful incorporation of an Ir^IIIphotoredox catalyst and a Ni^IIcross‐coupling catalyst into a stable Zr₁₂MOF, Zr₁₂‐Ir‐Ni, to efficiently catalyze C−S bond formation between various aryl iodides and thiols. The proximity of the Ir^IIIand Ni^IIcatalytic components to each other (ca. 0.6 nm) in Zr₁₂‐Ir‐Ni greatly facilitates electron and thiol radical transfers from Ir to Ni centers to reach a turnover number of 38 500, an order of magnitude higher than that of its homogeneous counterpart. This work highlights the opportunity in merging photoredox and organometallic catalysts in MOFs to effect challenging organic transformations.

Metal–organic frameworks (MOFs) have been extensively used for single‐site catalysis and light harvesting, but their application in multicomponent photocatalysis is unexplored. We report here the successful incorporation of an Ir^IIIphotoredox catalyst and a Ni^IIcross‐coupling catalyst into a stable Zr₁₂MOF, Zr₁₂‐Ir‐Ni, to efficiently catalyze C−S bond formation between various aryl iodides and thiols. The proximity of the Ir^IIIand Ni^IIcatalytic components to each other (ca. 0.6 nm) in Zr₁₂‐Ir‐Ni greatly facilitates electron and thiol radical transfers from Ir to Ni centers to reach a turnover number of 38 500, an order of magnitude higher than that of its homogeneous counterpart. This work highlights the opportunity in merging photoredox and organometallic catalysts in MOFs to effect challenging organic transformations.