Iron-complex-based catalytic system for high-performance water oxidation in aqueous media
Takumi Matsuzaki, Kento Kosugi, Hikaru Iwami, Tetsuya Kambe, Hisao Kiuchi, Yoshihisa Harada, Daisuke Asakura, Taro Uematsu, Susumu Kuwabata, Yutaka Saga, Mio Kondo, Shigeyuki Masaoka
Abstract
Water oxidation is the key reaction in natural and artificial photosyntheses but is kinetically and thermodynamically sluggish. Extensive efforts have been made to develop artificial systems comparable to the natural system. However, constructing a molecular system based on ubiquitous metal ions with high performance in aqueous media similar to a natural system, remains challenging. In this study, inspired by nature, we successfully achieve highly efficient water oxidation in aqueous media. By electrochemical polymerisation of a pentanuclear iron complex bearing carbazole moieties, we successfully integrate two essential features of the natural system: catalytic centre composed of ubiquitous metal ions and charge transporting site. The resulting material catalyses water oxidation with a Faradaic efficiency of up to 99% in aqueous media. Our results provide a strategy to develop catalytic systems for water oxidation. While water oxidation is the key reaction in natural and artificial photosynthesis, it is kinetically and thermodynamically sluggish, so constructing a molecular system in aqueous media remains challenging. Here, the authors report highly efficient water oxidation in aqueous media via electrochemical polymerisation of a pentanuclear iron complex.