Rational Design of Superior Photoelectrochemical System through Bioinspired Self-Assembly of Light-Harvesting Complexes

Deep understanding of the photoelectrochemical process of natural antenna complexes inspires us to rationally design novel artificial devices for various applications. Enlightened by natural photosynthesis, a photoelectrochemical system based on covalently linked light-harvesting complexes and plasmonic particles is designed for the purpose of obtaining superior photoelectrochemical performances and applications. It has been found that peridinin-chlorophyll-protein (PCP), a water-soluble light-harvesting antenna protein, could be well assembled and form closed, as well as ordered, arrangements on the surface of gold microplates via covalent linking, which results in excellent fluorescence enhancement. Further, the designed photoelectrochemical system not only presents improved light-harvesting ability and electric property but also displays over 14 times higher photocurrent performances than the photoelectrochemical system composed of unlinked and randomly distributed PCP complexes on the surface of gold microplates. We think the superior performances of the designed photoelectrochemical system are benefited from the enhanced light-harvesting ability, improved efficiency of electron generation, separation and transfer, abundant excited electrons, and excellent chemical and photoelectrochemical stability due to the self-assembly of PCP complexes and formation of close and ordered arrangements on the large plane surface of gold microplates via covalent linking. Significantly, our designed photoelectrochemical system presents very superior activity and promising applications in visible-light-driven water splitting, as its hydrogen generation speed is accelerated over 11 times that of the unlinked gold microplates and PCP complexes system. In a word, our research provides an effective way for preparing photoelectrochemical systems with excellent light-harvesting ability, great photoelectrochemical performances, and high stability, which has displayed practical application in water splitting for hydrogen generation. We believe that our results not only promote our understanding of fundamentals but also present prospective applications in many fields such as fluorescent sensors, photoelectrochemical devices, green energy, and artificial photosynthesis.