Microwave‐Assisted Quick Synthesis of Ru(II)‐Based Metallosupramolecular Polymer for Improved Electrochromic Properties

Abstract

AbstractMetallosupramolecular polymers (MSPs) have reversible electrochromic (EC) characteristics. Transition metal ions and ditopic organic ligands are complexed 1:1 to form MSPs, but the complexation conditions depend on the metal species ions. Herein, a microwave‐assisted (MWA) quick synthesis of a Ru(II)‐based MSP (polyRu–MWA) as a novel preparation method for MSPs is reported. PolyRu–MWA is synthesized under microwave irritation for 60 min using 770 W and 2.45 GHz frequency, whereas a conventionally synthesized Ru(II)‐based MSP (polyRu–CS) is obtained using oil‐bath at 160 °C for 24 h. PolyRu–MWA is found to show much better EC properties than polyRu–CS. A film of polyRu–MWA prepared on an indium tin oxide glass exhibits higher optical contrast (transmittance change, ΔT: 81.39%) than polyRu–CS (67.73%). Coloration efficiency(CE, η) of polyRu–MWA (425.7 cm2 C−1) is also higher than that of polyRu–CS (318.3 cm2 C−1). Interestingly, the charge and discharge current ratio for bleaching and coloring in polyRu–MWA is ≈1.7 times higher than that for polyRu–CS, probably because of the high molecular weight polymer formation in polyRu–MWA. A polyRu–MWA film also displays a longer EC optical memory than polyRu–CS.