A molecular precatalyst for water oxidation based on half-sandwich iridium fragment

•A newly precatalysis of water oxidation based on half-sandwich iridium linked by an azo-compound was synthesized.•TOF of the catalyst was quite a good, reaching up to 4692.1 M−1 S−1.•A heterogeneous catalyst was prepared by activated carbon absorbing the homogeneous catalyst.•Mechanism of the water oxidation catalyst was systematic studied in the work.

A newly Ir-mediated complex constructed by treating [Cp*IrCl2]2 with an azo-compound [sodium (E)-4-((3-hydroxynaphthalen-2-yl)diazenyl)benzenesulfonate (HL)], was fully characterized by NMR, EA, TGA, IR and single crystal X-ray diffraction to reveal its molecular structure with mononuclear framework. Cyclic voltammetry (CV) was performed on detecting its electronic properties, affording potential application of catalyzing water oxidation to evolve oxygen. Moreover, the complex utilized as precatalyst of WOC was preformed under mild conditions, offering a high turnover frequency (TOF) which reached up to 4692.1 M−1 S−1. Meanwhile, the mechanism of water-oxidation reaction was elaborated in detail in this work.

Graphical abstractA newly precatalyst for water oxidation based on half-sandwich iridium motif exhibited a highly efficiency reached up to 4692.1 M−1 S−1.Figure optionsDownload full-size imageDownload as PowerPoint slide