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The oxygen evolution reaction (OER) is a key step in artificial photosynthesis, and protons and electrons generated in the reaction are vital for subsequent cathodic reactions. In this paper, a lightassisted photoelectrocatalytic system constructed by the OER catalyst (tpyRubpy) and light-harvesting moiety (porphyrin) was further covalently grafted onto the multiwalled carbon nanotubes (MWCNTs). The formed nanocatalyst preserves both the high-efficiency catalytic OER performance of tpyRubpy and the light-harvesting performance of porphyrin, and the graft of MWCNT results in a decrease in the chargetransfer resistance of the composite electrode and achieved an excellent light-assisted electrocatalytic OER property with a lower onset potential of 1.57 V and a lower overpotential of 440 mV at a current density of 10 mA cm −2 . This photoelectrocatalytic system successfully opens a new avenue for the rational design and fabrication of artificial photosynthesis systems through a covalent assembly strategy that mimics the key functions of photosystem II.

Electrocatalytic oxygen evolution reaction (OER) plays an important role in various renewable energy conversion and storage technologies. Ruthenium complexes with terpyridine (tpy) and bipyridine (bpy) as ligands are considered to be an important catalyst for OER electrocatalysis. Their catalytic performance is affected by substituent groups of the tpy (and bpy) ligands, and is often limited by low current density. Here, we report a Ru‐polypyridine complex covalently anchored to single‐walled carbon nanotubes (SWCNTs) via a tpy ligand to form a hybrid material of SWCNT‐tpyRubpy. Electrocatalytic OER studies have shown that the covalent attachment of the Ru‐polypyridine complexes to SWCNTs avoids noticeable molecular aggregations and increases the conductivity. Compared with that of the SWCNT‐unattached complex, SWCNT‐tpyRubpy exhibits a higher electrocatalytic OER activity with a low onset potential of 1.48 V (vs reversible hydrogen electrode) and a smaller Tafel slope of 109 mV dec−1 in alkaline solution. Therefore, the CNT‐hybridization is an effective method for the construction of advanced SWCNT‐based Ru complex electrocatalysts and to understand their catalytic performance.