1. Institute of Materials for Energy and Environment College of Materials Science and Engineering Qingdao University Qingdao 266071 P.R. China
2. State Key Laboratory of Bio-Fibers and Eco-Textile Qingdao University Qingdao 266071 P.R. China
3. College of Chemistry and Chemical Engineering Qingdao University Qingdao 266071 P.R. China
4. College of Electromechanic Engineering Qingdao University Qingdao 266071 P.R. China