Premium
Engineered Electron‐Transfer Chain in Photosystem 1 Based Photocathodes Outperforms Electron‐Transfer Rates in Natural Photosynthesis
Author(s) -
Kothe Tim,
Pöller Sascha,
Zhao Fangyuan,
Fortgang Philippe,
Rögner Matthias,
Schuhmann Wolfgang,
Plumeré Nicolas
Publication year - 2014
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201402585
Subject(s) - electron transfer , photosynthetic reaction centre , artificial photosynthesis , photocurrent , redox , electron acceptor , electron transport chain , photosystem i , photosystem ii , photochemistry , p680 , chemistry , photosynthesis , electron donor , p700 , materials science , chemical physics , optoelectronics , photocatalysis , inorganic chemistry , organic chemistry , catalysis , biochemistry
Photosystem 1 (PS1) triggers the most energetic light‐induced charge‐separation step in nature and the in vivo electron‐transfer rates approach 50 e − s −1 PS1 −1 . Photoelectrochemical devices based on this building block have to date underperformed with respect to their semiconductor counterparts or to natural photosynthesis in terms of electron‐transfer rates. We present a rational design of a redox hydrogel film to contact PS1 to an electrode for photocurrent generation. We exploit the pH‐dependent properties of a poly(vinyl)imidazole Os(bispyridine) 2 Cl polymer to tune the redox hydrogel film for maximum electron‐transfer rates under optimal conditions for PS1 activity. The PS1‐containing redox hydrogel film displays electron‐transfer rates of up to 335±14 e − s −1 PS1 −1 , which considerably exceeds the rates observed in natural photosynthesis or in other semiartificial systems. Under O 2 supersaturation, photocurrents of 322±19 μA cm −2 were achieved. The photocurrents are only limited by mass transport of the terminal electron acceptor (O 2 ). This implies that even higher electron‐transfer rates may be achieved with PS1‐based systems in general.