《Surface-Enhanced Counter Electrode Materials for the Fabrication of Ultradurable Electrochromic Devices》 was written by Ahmad, Rana; DiPalo, Vittoria-Ann; Bell, Mackenzie; Ebralidze, Iraklii I.; Zenkina, Olena V.; Easton, E. Bradley. Quality Control of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine And the article was included in ACS Applied Energy Materials on April 25 ,2022. The article conveys some information:
Electrochromic devices (ECDs) and especially electrochromic supercapacitors, where the real-time state of charge is indicated by the color, have a wide range of applications. However, to meet modern challenges, these devices should demonstrate exceptional charge-discharge durability. In this work, we demonstrate that electrochem. cycling stability of ECDs based on a monolayer of 4′-(4-pyridyl)-2,2′:6′,2′′-terpyridine-iron(II) complex that was covalently linked to the working electrode (WE) can be drastically enhanced by a proper design of the counter electrode (CE). Enhancing the surface area of the flat indium tin oxide (ITO) CE by a layer of screen-printed ITO nanoparticles results in an ECD that upon continuous spectro-electrochem. switching for 600 cycles demonstrates negligible deterioration of the change in optical d. The enhanced surface area of the CE significantly diminishes the electrode and gel electrolyte degradation and allows us to gain fundamental insight into the pathway of degradation of the electrochromic mols. at the WE. During prolonged cycling (20,000 and 50,000 cycles), the overall total resistance of ECDs remains fairly unchanged, while the capacitance decreases due to a loss of the pseudocapacitive component associated with electrochromic mols. XPS suggests that this loss is likely due to the cleavage of the linkage C-N+ bond followed by the dissolution of the entire metal complex mol. into the electrolyte. In the experiment, the researchers used 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3Quality Control of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine)
4′-(4-Pyridyl)-2,2′:6′,2”-terpyridine(cas: 112881-51-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Quality Control of 4′-(4-Pyridyl)-2,2′:6′,2”-terpyridineThe lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds.