1. Department of Chemistry, Royal Holloway, University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom, School of Chemical Science, Shaanxi University of Science and Technology, Xianyang, Shaanxi, People's Republic of China, and British School of Leather Technology, University College Northampton, Boughton Green Road, Northampton NN2 7AL, United Kingdom