Optoelectronic properties of a photosystem I - carbon nanotube hybrid system

TL;DR

This study demonstrates the integration of photosystem I proteins with carbon nanotubes to create hybrid systems with controllable photoconductance, advancing nanoscale optoelectronic device development.

Contribution

The paper introduces a method for covalently binding photosystem I to carbon nanotubes, enabling control of photoconductance in hybrid nanoscale optoelectronic systems.

Findings

Enhanced photoconductance at PSI absorption wavelengths

Successful covalent binding of PSI to CNTs

Feasibility of integrating photosynthetic proteins into electronic circuits

Abstract

The photoconductance properties of photosystem I (PSI) covalently bound to carbon nanotubes (CNTs) are measured. We demonstrate that the PSI forms active electronic junctions with the CNTs enabling control of the CNTs photoconductance by the PSI. In order to electrically contact the photoactive proteins, a cysteine mutant is generated at one end of the PSI by genetic engineering. The CNTs are covalently bound to this reactive group using carbodiimide chemistry. We detect an enhanced photoconductance signal of the hybrid material at photon wavelengths resonant to the absorption maxima of the PSI compared to nonresonant wavelengths. The measurements prove that it is feasible to integrate photosynthetic proteins into optoelectronic circuits at the nanoscale.