Enhancing the Electrochromic Properties of Polyaniline through Incorporating Terpyridine Units and Coordination Bonding with Transition Metal Ions

Abstract

AbstractA novel polyaniline‐terpyridine‐transition metal ions (PANI‐TPY−M (M=Fe (II), Co (II), Ni (II))) hybrid electrochromic materials containing coordination bonds were successfully synthesized in an aqueous medium. The molecular and aggregation structures of PANI‐TPY−M were systematically studied by FTIR (Fourier transform infrared spectroscopy), particle size analysis and Raman spectroscopy. The influence of transition metal ions on the thermal stability of materials was analyzed by TGA (thermogravimetric analysis). The electrochemical behaviors and electrochromic properties of materials were measured by CV (cyclic voltammetry) and UV‐vis (UV‐visible spectroscopy). It can be found that the electrochemical activities of PANI‐TPY and PANI‐TPY−M are both higher than that of PANI. Especially, the electrochromic devices with PANI‐TPY−M (M=Fe (II), Co (II), Ni (II)) as active layer exhibit obvious optical contrast enhancement function. As comparison to PANI, the contrast of PANI‐TPY increases about 57%, the contrast of PANI‐TPY−Fe increases about 76%, the contrast of PANI‐TPY−Co increases by nearly 73%, and the contrast of PANI‐TPY−Ni increases by 54%.