1. School of Materials Science and Engineering, Anhui University of Science and Technology, Huainan, Anhui 232001, P. R. China
2. Anhui International Joint Research Center for Nano Carbon-based Materials and Environmental Health, Huainan, Anhui 232001, P. R. China
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan, 410083, P. R. China
4. Sino-Precious Metals Holding Co., Ltd, Kunming, 650000, P. R. China