The Properties of electrochromic film electrodes of lanthanide diphthalocyanines in ethylene glycol

The electrochromic properties of film electrodes of lutetium, erbium, gadolinium, and ytterbium diphthalocyanines in contact with ethylene glycol solutions have been studied. The stability of the electrochromic film under electrochemical cycling in this medium is at least three orders of magnitude better than that in neutral aqueous solutions. The stability of the electrochromic is improved if the film is written galvanostatically from the yellow-tan to the green state. A simplified model for the galvanostatic transition is proposed, and some of the problems of this family of electrochromic materials are discussed. © 1985, The Electrochemical Society, Inc. All rights reserved.