In the Dye Sensitized Solar Cell (DSSC) the dye sensitizer carries out the light harvesting function and is therefore crucial in determining overall cell efficiency. In addition, the dye sensitizer can influence many of the key electron transfer processes occurring at the TiO(2)/dye/electrolyte interface which also determine efficiency. Dye structure can influence and drive forward electron injection into the conduction band of the TiO(2). Conversely, dye structure can help retard loss electron transfer processes such as charge recombination of injected electrons in the TiO(2) with dye cations and also recombination of these electrons with the electrolyte. Therefore tuning dye sensitizer light absorbing properties and control of the aforementioned electron transfer processes through structural design of the dye sensitizer is an important avenue through which optimization of DSSC efficiency should be pursued. In this critical review the latest work focusing on the design of dyes for efficient DSSCs is revised (111 references).

Solvent vapour annealing (SVA), which consists of exposing the active layer of organic films to a vapour of solvent directly after deposition, has been used in small molecule bulk heterojunction (SM-BHJ) solar cell devices whose active layer consisted of 3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)pyrrolo [3,4-c]pyrrole-1,4-dione (DPP(TBFu) 2 ) and [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM). We demonstrate that upon SVA, well-ordered crystalline domains of the DPP(TBFu) 2 donor form inside the active layer, improving greatly the Fill Factor (FF) of the devices. However, SVA treatment is always accompanied by a decrease in device short circuit current (J SC ). We demonstrate, using 1D and 2D XRD and AFM, that crystalline domains of DPP(TBFu) 2 form in a matrix of PC 71 BM acceptor. The crystallinity increases with annealing time (t a ) and the change in FF and J SC is directly linked to this. The X-ray single crystal structure of the DPP(TBFu) 2 donor was solved and provided information of the donor's packing in the solid state. The donor molecules were shown to pack in a herringbone arrangement and shown to form a highly texturized active layer film. We demonstrated that the ability of the donor to form large and highly texturized crystalline domains in the active layer is as equally as determining for the devices' characteristics as the individual stacking properties of the donor in the solid state.

Ring of protection: A [2]rotaxane 1 protects and selectively releases a bioactive pentapeptide. The rotaxane macrocycle provides a defensive shield that very significantly improves the poor stability of the peptide to both individual peptidases and the cocktail of enzymes present in human plasma. Glycosidase‐catalyzed cleavage of a carbohydrate ‘stopper’ in the rotaxane triggers release of the parent peptide (see picture).

Schützender Ring: Das [2]Rotaxan 1 kann ein bioaktives Pentapeptid schützen und selektiv freisetzen. Der Makrocyclus des Rotaxans stabilisiert das empfindliche Peptid sowohl gegen einzelne Peptidasen als auch gegen eine Enzymmischung aus Humanplasma. Die durch Glycosidase katalysierte Abspaltung einer Kohlenhydrat‐Endgruppe, die im Rotaxan als Stopper wirkt, führt zur Freisetzung des Peptids (siehe Bild).