1. Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province; Shantou University; Guangdong 515063 P. R. China
2. Department of Chemistry; The University of Hong Kong, Pokfulam Road; Hong Kong S. A. R. P. R. China
3. Instituto de Tecnología Química UPV-CSIC; Universitat Politècnica de València, Consejo Superior de Investigaciones Científicas; Avda de los Naranjos s/n 46022 Valencia Spain