Carbon Carbon Graphene-NHC-iridium hybrid catalysts built through -OH covalent linkage Dedicated to the lasting Memory of Prof. Dr. María Pilar García for her valuable talent as human, teacher and chemist Blanco Matías Álvarez Patricia Blanco Clara Jiménez M. Victoria Universidad de Zaragoza Fernández-Tornos Javier Pérez-Torrente Jesús J. Universidad de Zaragoza Oro Luis A. Universidad de Zaragoza Menéndez Rosa 2015 research-article