Near-IR Electrochromic Film Prepared by Oxidative Electropolymerization of the Cyclometalated Pt(II) Chloride with a Triphenylamine Group

Abstract

A cyclometalated platinum chloride [(L)PtCl] {L = 4-[p-(diphenylamino)phenyl]-6-phenyl-2,2'-bipyridine} was successfully synthesized and characterized by (1)H NMR, (13)C NMR, MALDI-TOF MS, elemental analysis, and X-ray crystallography. Its oxidative electropolymerization proceeds smoothly on the working Pt and ITO electrodes by cyclic voltammetry. The film thickness can be easily tuned by controlling the CV scan number. The orange hybrid polymer film shows the nondiffusion-controlled redox processes and a unusually inverse dependence of ac impedance on its thickness. As a result of switching of the MLCT/ICT and dication absorption transitions, the adherent metallopolymer film exhibits the low-voltage-controlled anodic coloration near-IR electrochromism with significant optical contrast ratio (ΔT% = 88.8% at 820 nm), fast response time (1.9 s for the coloration step and 2.3 s for the bleaching step), and high coloration efficiency (CE = 363.3 C(-1)·cm(2)).

Unusual Photoelectrochemical Properties of Electropolymerized Films of a Triphenylamine-Containing Organic Small Molecule

“…Among these techniques, electropolymerization presents the following competitive advantages: easy operation, cost-effective instrumentation, very rapid simultaneous realization of electrosynthesis of polymers and separation of the polymers and monomers, controllable film coverage and thickness, and varying structures and doping degrees by simply changing electropolymerization parameters, such as electropolymerization time or the number of potential sweep cycles and precursor molecules, , although spin coating and electrospray have been used in industry for film fabrication. It has been shown that vinyl, , thiophene, pyrrole, carbazole, and aromatic amine or triphenylamine (TPA) group − containing functional molecules could be cathodically/anodically electropolymerized onto conductive electrode surfaces. Of these electropolymerizable materials, TPA and its derivative-based organic and metal complexes have attracted special attention for electropolymerized films with many applications in some photoelectronic devices, such as solar cells, electrocatalytic and photoelectrochemical devices, memory devices, sensors, and electrochromic and electroluminescent devices. ,,,,,,− …”

Unusual Reactivity and Photophysical Properties of Platinum(II) Pincer Complexes Containing 6,6'‐Diphenyl‐2,2'‐bipyridine Ligands

“…Experimental and calculated structural characteristics are in good agreement that indicates suitability of selected calculation approach. The complexes obtained display slightly distorted square‐planar geometry, where the multidentate ligand is coordinated in the NNC mode, which is typical for platinum(II) complexes containing phenyl‐bipyridyl coordinating moiety, [ 18,27–30 ] whereas the chloride ligand occupies the fourth coordination position. The coordinated aromatic systems of the NNC‐ligand forms nearly planar configuration with the major structural characteristics similar to those found in the other platinum complexes of the [Pt(NNC–R)L] type.…”

“…The coordinated aromatic systems of the NNC-ligand forms nearly planar configuration with the major structural characteristics similar to those found in the other platinum complexes of the [Pt(NNC-R)L] type. [18,[28][29][30] The values of bond lengths Pt 1 -C 1 ca. 2.7 Å are nearly identical for all these compounds.…”

Electrochromic Conjugated Polymers for Multifunctional Smart Windows with Integrative Functionalities

“…Recently, metal complexes with terpyridine‐triphenylamine ligands were reported to realize various color and long optical memory using different ligands: L1 (4‐(2,2′:6′,2″‐terpyridinyl)triphenylamine), [ 68 ] L2 (4‐[4‐(2,2′:6′,2″‐terpyridinyl)]phenyltriphenylamine), [ 69 ] and L3 (4‐[4‐(2,2′:6′,2″‐terpyridinyl)] styryltriphenylamine). [ 70 ] These ligands contain TPA donors and terpyridine acceptor, which were connected through phenyl, biphenyl, or stilbene as the π‐bridge (π), to build “D−π–A−π–D”‐type complexes (MLn).…”