Molecular engineering of sensitizers for dye‐sensitized solar cell applications

Abstract

Dye-sensitized solar cells (DSSCs) have attracted considerable attention in recent years as they offer the possibility of low-cost conversion of photovoltaic energy. This account focuses on recent advances in molecular design and technological aspects of sensitizers based on metal complexes, metal-free organics and tetrapyrrolic compounds which include porphyrins, phthalocyanines as well as corroles. Special attention has been paid to the design principles of these dyes, and co-sensitization, an emerging technique to extend the absorption range, is also discussed as a way to improve the performance of the device. This account also focuses on recent advances of efficient ruthenium sensitizers as well as other metal complexes and their applications in DSSCs. Recent developments in the area of metal-free organic and tetrapyrrolic sensitizers are also discussed.

Triphenylamine-functionalized corrole sensitizers for solar-cell applications

“…However, ruthenium complexes are exclusive due to rarity, tedious purification methods and lack of absorption in the near‐IR region of the solar spectrum. For this reason intensive investigations have been carried out into alternative sensitizers such as metal‐free organic dyes and closed ring structures like porphyrins and phthalocyanines . Significantly, a porphyrin dye has recently shown photovoltaic conversion efficiencies exceeding 13%, in combination with a Co (II)/Co (III) redox electrolyte .…”

Near-infrared absorbing unsymmetrical Zn(II) phthalocyanine for dye-sensitized solar cells

“…, Zn 2 etc., and metal-free organic sensitizers have been designed for DSCs applications [15,16]. The highest reported DSCs efficiency exceeding 12% has been achieved by a Zn(II)…”

Sterically demanded unsymmetrical zinc phthalocyanines for dye-sensitized solar cells

“…In this regard, solar energy is expected to play a key role in sustainable development [1]. Among the various photovoltaic technologies, dye-sensitized solar cells, (DSSC) have emerged alongside conventional p-n junction solar cells [2][3][4]. In a typical DSSC, upon photo excitation, the dye injects an electron into the conduction band of a nanocrystalline film of a wide-band-gap oxide semiconductor, such as titanium dioxide (TiO 2 ), and is subsequently regenerated back to the ground state by electron donation from a redox couple.…”