1 Effect of Cu-doped graphene on the flammability and thermal properties of epoxy composites Yun Liu a,b , Heeralal Vignesh Babu b , Jianqing Zhao c , Asier Goñi-Urtiaga d , Raquel Sainz d , Rafael Ferritto d , Marcos Pita e , De-Yi Wang b * a. College of Chemistry and Chemical Engineering, Wuhan Textile University, Fangzhi Road, 1, Wuhan 430073, China. b. IMDEA Materials Institute, C/Eric Kandel, 2, Getafe, Madrid, 28906, Spain c. School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510006, China d. Nanoinnova Technologies S.L., Parque Científico de Madrid, C/Faraday 7, Madrid, 28049, Spain. e. Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, 280409 Madrid, Spain. Corresponding author: De-Yi Wang: Tel.: +34-917871888, E-mail address: deyi.wang@imdea.org