Engineering Cascade Bio-solar Cells Inspired by the Z-Scheme of Oxygenic Photosynthesis: Layered Chlorophyll and Bacterio-chlorophyll Derivatives.

The natural Z-scheme of oxygenic photosynthesis efficiently drives electron transfer from photosystem II (PSII) to photosystem I (PSI) via an electron transport chain, despite the lower energy levels of PSII. Inspired by this sophisticated mechanism, we present a layered cascade bio-solar cell (CBSC) that emulates the Z-scheme. In this design, chlorophyll derivatives (Chl) act as PSI analogs, while bacteriochlorophyll derivatives (BChl) serve as PSII analogs in the active layer.

Astaxanthin: Past, Present, and Future.

Astaxanthin (AX), a lipid-soluble pigment belonging to the xanthophyll carotenoids family, has recently garnered significant attention due to its unique physical properties, biochemical attributes, and physiological effects. Originally recognized primarily for its role in imparting the characteristic red-pink color to various organisms, AX is currently experiencing a surge in interest and research. The growing body of literature in this field predominantly focuses on AXs distinctive bioactivities and properties.

Excited-State Dynamics of All the Mono- and the Major Di- Isomers of β-Apo-8'-Carotenal as Revealed by Femtosecond Time-Resolved Transient Absorption Spectroscopy.

isomers of carotenoids play important roles in light harvesting and photoprotection in photosynthetic bacteria, such as the reaction center in purple bacteria and the photosynthetic apparatus in cyanobacteria. Carotenoids containing carbonyl groups are involved in efficient energy transfer to chlorophyll in light-harvesting complexes, and their intramolecular charge-transfer (ICT) excited states are known to be important for this process. Previous studies, using ultrafast laser spectroscopy, have focused on the central- isomer of carbonyl-containing carotenoids, revealing that the ICT excited state is stabilized in polar environments.