Graphene-poly(nickel complex) as novel electrochromic nanocomposite for the fabrication of a robust solid-state device

Abstract

An electrochromic nanocomposite based on a nickel-salen polymeric film - poly[Ni(3-Mesalen)], Mesalen=N,N'-bis(3-methylsalicylideneiminate) - and graphene nanoplatelets (GFNPs) with enhanced electrochromic stability was successfully prepared by anodic electropolymerization. Although the electrochemical processes typical of the polymer film were not changed by the presence of graphene, higher electroactive surface coverages could be obtained for nanocomposite films, which suggest the incorporation of GFNPs into the polymeric network. The nanocomposite showed multi-electrochromic behavior, with color changes between yellow (reduced state) and green (oxidized state). The inclusion of GFNPs into the poly[Ni(3-Mesalen)] structure accelerates the switching process, with the response time for green coloration decreasing by 50.7% and for yellow coloration by 60.0%, for films prepared with 30 electropolymerization cycles. In terms of electrochemical stability, after 10,000 electrochemical cycles the loss of charge was 7% for the graphene nanocomposite. The nanocomposite film was used as electrochromic material to assemble a flexible solid-state electrochromic device (ECD), which exhibited an outstanding electrochemical stability - only 3% of charge loss after 15days of continuous activity.

Facile Fabrication of Triphenylamine‐Based Redox‐Active Nanocomposites by a Sol‐Gel Method: Enhanced Electrochromic Response Capability and Stability Performance

“…Recently, hybrid EC materials incorporating inorganic solids into electroactive polymers have been rapidly developed, especially for metal oxides such as titanium(IV) oxide (TiO 2 ), zirconium(IV) oxide (ZrO 2 ), and WO 3 . Additionally, conductive nanomaterials such as carbon nanotubes, graphene, gold, and silver nanowires are good candidates for EC hybrid materials …”

Atomic and Electronic Structure of Metal–Salen Complexes [M(Salen)], Their Polymers and Composites Based on Them with Carbon Nanostructures: Review of X-ray Spectroscopy Studies

“…The literature provides several key methods for forming composites of MWCNTs (SWCNTs), graphene, and electrically conductive polymers based on [Ni(Salen)] complexes by electrochemical deposition. One approach is to prepare a conductive electrode with a carbon layer that serves as a substrate for the formation of a polymer, such as poly-[Ni(Salen)] [5,7,42,113,114] [42], by using a solution consisting of an electrolyte and a monomer and applying potentiodynamic, conventional, or pulsed potentiostatic methods. In the studies referred to, it was mainly MWCNTs that were used as the carbon material, with the preparing composites serving as materials for energy storage.…”

“…An alternative method involves codepositing polymer and carbon material from a mixture of a monomer solution in an electrolyte and a suspension of carbon material, followed by the formation of a composite coating on a conductive electrode [58]. Poly-[Ni(Salen)]/MWCNTs [9], poly-[Ni(3-CH 3 O-Salen)]/graphene [114], and poly-[Ni(3-CH 3 O-Salen)]/N-FLG (nitrogendoped few-layer graphene) [37] composite films were synthesized using this method. However, this approach has a number of disadvantages associated both with obtaining a uniform dispersion of carbon nanomaterials and with the reproducibility of the structure and, accordingly, the characteristics of the composite.…”

“…Research in recent years has been characterized by individual attempts to use the XPS method to obtain information on the chemical state of functional atoms in monomers and their poly-[M(Salen)] polymers, as well as on the atomic structure of these polyatomic systems [26,39,[43][44][45][46][48][49][50][51][52]114]. It should be noted that all the cited measurements of XPS spectra are mainly of a test nature, and most of them were performed on laboratory installations using X-ray tubes as radiation sources with low energy resolution and insuffi- It is important to note that X-ray absorption (NEXAFS, EXAFS) spectra can be measured in various modes such as transmission and fluorescence as well as total electron and Auger electron yield modes.…”

Fundamentals and Advances of Electrochromic Systems: A Review

“…Cyclic Voltammetry One of the most important analyses in studying electrochemical and optoelectrochemical properties of EC systems is cyclic voltammetry (CV). [82,108,114,118,121,[125][126][127][128][129] In this technique, the variation of current density versus applied external voltage is recorded periodically in an electrochemical cell. Considering the type of system under study and the purpose of using this analysis, the EC cell can include two or three electrodes in which, in all cases, EC layer is used as WE in the vicinity of the electrolyte.…”