Ligand (biochemistry)

Electrical engineering

Physics

Receptor

Electrode

Organic chemistry

Combinatorial chemistry

Bipyridine

Crystal structure

Optics

Absorption (acoustics)

Software engineering

Absorption spectroscopy

Engineering

Catalysis

Physical chemistry

Composite material

Chemistry

Metallurgy

Materials science

Design elements and principles

Computer science

Photovoltaic system

Metal

Electrolyte

Terpyridine

Dye-sensitized solar cell

Biochemistry

Ruthenium

Photochemistry

Materials

Terpyridine and quaterpyridine-based complexes allow wide light harvesting of the solar spectrum. Terpyridines, with respect to bipyridines, allow for achieving metal-complexes with lower band gaps in the metal-to-ligand transition (MLCT), thus providing a better absorption at lower energy wavelengths resulting in an enhancement of the solar light-harvesting ability. Despite the wider absorption of the first tricarboxylate terpyridyl ligand-based complex, Black Dye (BD), dye-sensitized solar cell (DSC) performances are lower if compared with N719 or other optimized bipyridine-based complexes. To further improve BD performances several modifications have been carried out in recent years affecting each component of the complexes: terpyridines have been replaced by quaterpyridines; other metals were used instead of ruthenium, and thiocyanates have been replaced by different pinchers in order to achieve cyclometalated or heteroleptic complexes. The review provides a summary on design strategies, main synthetic routes, optical and photovoltaic properties of terpyridine and quaterpyridine ligands applied to photovoltaic, and focuses on n-type DSCs.

Terpyridine and Quaterpyridine Complexes as Sensitizers for Photovoltaic Applications