Regeneration of Light-Harvesting Complexes via Dynamic Replacement of Photodegraded Chromophores.

ACS Appl Mater Interfaces

†School of Mechanical Engineering and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.

Published: April 2015

All-synthetic molecular donor-acceptor complexes are designed, which are capable of counteracting the effect of photoinduced degradation of donor chromophores. Anionic gallium protoporphyrin IX (GaPP) and semiconducting carbon nanotube (CNT) are used as a model donor-acceptor complex, which is assembled using DNA oligonucleotides. The GaPP-DNA-CNT complex produces an anodic photocurrent in a photoelectrochemical cell, which steadily decays due to photo-oxidation. By modulating the chemical environment, we showed that the photodegraded chromophores may be dissociated from the complex, whereas the DNA-coated carbon nanotube acceptors are kept intact. Reassociation with fresh porphyrins leads to the full recovery of GaPP absorption and photocurrents. This strategy could form a basis for improving the light-harvesting performance of molecular donor-acceptor complexes and extending their operation lifetime.

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http://dx.doi.org/10.1021/acsami.5b01924DOI Listing

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