Ultrafast Electron Transfer in Au–Cyanobacteria Hybrid for Solar to Chemical Production
Qiushi Hu, Haitao Hu, Lei Cui, Zhaodong Li, Draženka Svedružić, Jeffrey L. Blackburn, Matthew C. Beard, Jun Ni, Wei Xiong, Xiang Gao, Xihan Chen
Abstract
The rise of inorganic–biohybrid organisms for solar-to-chemical production has spurred mechanistic investigations into the dynamics of the biotic–abiotic interface to drive the development of next-generation hybrid systems. The model system, cyanobacteria–gold nanoparticle hybrids, combines a light harvester with a photosynthetic bacterium to drive the reduction of CO2 to glycerol with improved efficiency and increased glycerol production by 14.6%, in comparison to cyanobacteria only. In this work, we report insights into this unique photochemical behavior and propose a charge-transfer pathway from Au nanoparticle to cyanobacteria. Transient absorption (TA) spectroscopy revealed that photoexcited electron transfer rates are on the order of a few ps to the potential electron acceptor in photosystem II. This work represents a promising platform to utilize a conventional spectroscopic methodology to extract insights from more complex biotic–abiotic hybrid systems.