Supramolecular catalyst with [FeCl4] unit boosting photoelectrochemical seawater splitting via water nucleophilic attack pathway
Jiaming Miao, Cheng Lin, Xiaojia Yuan, Yang An, Yan Yang, Zhaosheng Li, Kan Zhang
Abstract
Abstract Propelled by the structure of water oxidation co-catalysts in natural photosynthesis, molecular co-catalysts have long been believed to possess the developable potential in artificial photosynthesis. However, the interfacial complexity between light absorber and molecular co-catalyst limits its structural stability and charge transfer efficiency. To overcome the challenge, a supramolecular scaffold with the [FeCl 4 ] catalytic units is reported, which undergo a water-nucleophilic attack of the water oxidation reaction, while the supramolecular matrix can be in-situ grown on the surface of photoelectrode through a simple chemical polymerization to be a strongly coupled interface. A well-defined BiVO 4 photoanode hybridized with [FeCl 4 ] units in polythiophene reaches 4.72 mA cm −2 at 1.23 V RHE , which also exhibits great stability for photoelectrochemical seawater splitting due to the restraint on chlorine evolution reaction by [FeCl 4 ] units and polythiophene. This work provides a novel solution to the challenge of the interface charge transfer of molecular co-catalyst hybridized photoelectrode.