Natural photosystems have been hybridized with electronic and electrochemical platforms for solar energy conversion applications. Photosystem I (PSI) is an attractive target due to its high internal quantum efficiency, adaptability, simple extraction, and thermal stability. However, the hybrid solar (fuel) cells often exhibit a low external efficiency because it is very challenging to optimize its orientation and interfaces for efficient charge transfer. Here, we introduce a PSI-carbon nitride hybrid electrode with a favorable orientation for electron transfer for efficient solar energy conversion. Protonated carbon nitride (PCN) nanosheets can be electrostatically complexed with PSI to form a hybrid structure. A heterojunction is formed in the hybrid structure, enabling electron transfer from the conduction band of PCN to PSI. The lifetime of photoelectrons generated in the PSI increased, resulting in ~ 28 times higher photocurrent from the PSI-PCN hybrid compared to that from PSI. The introduction of PCN also expands the light absorption spectrum, which contributes to the increased photocurrent as demonstrated in photocurrent spectrum analysis. This study demonstrates that the well-oriented hybridization of PSI with carbon nanostructures provides us with an insight for the construction of nano-hybrid materials for efficient energy conversion.

Natural photosystems and protonated carbon nitride nanosheets hybrid structures for solar energy conversion

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.