New Insight into the Fatigue Resistance of Photochromic 1,2-Diarylethenes

Abstract

Photochromic diarylethenes represent one of the most important classes of molecular switches, and their fatigue resistance is reported in several papers. Previous studies have demonstrated that the presence of perfluorocyclopentene and methyl in the 4-positions of dithienylethenes improve the switching resistance. However, general guidelines to correlate chemical structure to fatigue resistance have not been found yet. In this work, we provide a different thought in the description of the fatigue resistance of diarylethenes, which is related to the light absorbed by the two isomeric states during photoconversion. For two series of 1,2-diarylethenes, which differ from the aromatic rings without bearing any electroactive substituent, it turns out that the fatigue resistance depends on the dose of light absorbed by the colored form rather than on the specific molecular structure, namely, the presence of specific molecular building blocks.

Structure–function relationships of donor–acceptor Stenhouse adduct photochromic switches

“…In addition to the commercial applications such as in sunglass lenses, photochromic molecules allow light to be used to reversibly control molecular properties for the development of light-controllable molecular tools, 3 controlling energy transfer 4 or self-assembly, 5 acting as receptors, 6 powering molecular machines, 7 for drug delivery, 8 or modifying material properties. 9 Dithienylethene, 10 spiropyran, 5 , 11 oxazine 12 and azobenzene 9a , 13 are classic photochromic molecules and examples exist in all of these groups where visible light can be used to drive the photoisomerisation. More recently, hemithioindigo, 14 indigos, 15 heterodiazocines, 16 arylhydrazones, 17 azo-BF 2 derivatives, 18 imidazolyl-based radicals 19 and coumarin-dienes 20 have all demonstrated excellent visible-light switching properties, including examples of biphotochromic systems.…”

Dual-responsive “smart” window and visually attractive coating based on a diarylethene photochromic dye

“…S2): degradation could play a role in this as well as other mechanisms such as crystallization and dye reorientation. Degradation mechanisms of this class of dyes have been extensively studied in the literature: [38][39][40][41][42] the dye host has a significant impact on stability. [43] Overall improvements in the dye lifetime will be necessary before it may be widely used in applications but extended switching capabilities have already been demonstrated.…”

Holography with Photochromic Diarylethenes

“…Fixed the quantum yield of the transformations (ϕCOUV,ϕOCUV), the time required to reach a stationary situation decreases while increasing the ratio εOUV/εCUV. It has been also demonstrated that this ratio affects the fatigue resistance of the diarylethenes [51].…”