1. Laboratoire de Chimie des Polymères Organiques, Université Bordeaux 1, CNRS-ENSCPB, 16 Avenue Pey-Berland, 33607 Pessac Cedex, France
2. New Materials Department, CIDETEC-Centre for Electrochemical Technologies, Parque Tecnológico de San Sebastián, Paseo Miramón 196, San Sebastian, E-20009, Spain