| Autor: |
Laschuk NO; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Ebralidze II; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Poisson J; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Egan JG; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Quaranta S; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Allan JTS; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Cusden H; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Gaspari F; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Naumkin FY; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Easton EB; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada., Zenkina OV; Faculty of Science , University of Ontario Institute of Technology , 2000 Simcoe Street North , Oshawa , Ontario L1H 7K4 , Canada. |
| Abstrakt: |
In this study, we present a range of efficient highly durable electrochromic materials that demonstrate excellent redox and lifetime stability, sufficient coloration contrast ratios, and the best-in-class electron-transfer constants. The materials were formed by anchoring as little as a monolayer of predefined iron complexes on a surface-enhanced conductive solid support. The thickness of the substrate was optimized to maximize the change in optical density. We demonstrate that even a slight change in molecular sterics and electronics results in materials with sufficiently different properties. Thus, minor changes in the ligand design give access to materials with a wide range of color variations, including green, purple, and brown. Moreover, ligand architecture dictates either orthogonal or parallel alignment of corresponding metal complexes on the surface due to mono- or bis-quaternization. We demonstrate that monoquaternization of the complexes during anchoring to the surface-bound template layer results in redshifts of the photoabsorption peak. The results of in-solution bis-methylation supported by density functional theory calculations show that the second quaternization may lead to an opposite blueshift (in comparison with monomethylated analogs), depending on the ligand electronics and the environmental change. It is shown that the variations of the photoabsorption peak position for different ligands upon attachment to the surface can be related to the calculated charge distribution and excitation-induced redistribution. Overall, the work demonstrates a well-defined method of electrochromic material color tuning via manipulation of sterics and electronics of terpyridine-based ligands. |
