Coupling photosystem II with Pt-decorated CdSe@CdS nanorods for water splitting

 

Abstract:

Photosynthesis is the most important solar-energy conversion process in nature. This process supports all life on earth and still has been studied extensively. Semiconductor nanoparticles with typical optical features can be used as a hybrid synthetic-biological system for photocatalytic water splitting. By consuming minimal resources, clean and renewable energy can be produced. We have previously shown that isolated Photosystem II (PSII) can be attached to gold-nanoparticles to harvest electrical current (Shoyhet et al. J. Mat. Chem. A 2021). Here we wish to improve this system to obtain total water splitting with a broad absorption cross section. For this goal, we extracted thylakoid membranes from the desert green algae Chlorella ohadii, that contain embedded PSII and synthesized in collaboration with the photocatalytic lab of Prof. Lilac Amirav from our Faculty a well- controlled nanoparticle-based artificial system. These particles are Pt-decorated CdSe@CdS nanorods that are made of cadmium selenide seed and a cadmium sulfide rod with a Pt-reduction catalyst placed on the opposite end of the rod that promotes charge separation and acts as an active site for hydrogen reduction. The conjugation with PSII was done by using an artificial PSII electron acceptor, DCBQ, that acts as an electron shuttle.

This seminar will discuss some of the results related to our efforts to design this hybrid system and the associated challenges.