1. Collaborative Innovation Center for Nanomaterials & Devices, College of Physics, Qingdao University, Qingdao 266071, China
2. Instrumental Analysis Center of Qingdao University, Qingdao 266071, China
3. Research Center for Intelligent & Wearable Technology, College of Textiles & Clothing, Qingdao University, Qingdao 266071, China
4. Center for Nanofibers & Nanotechnology, Faculty of Engineering, National University of Singapore, Singapore 119007, Singapore
5. State Key Laboratory of Bio-Fibers & Eco-Textiles (Qingdao University), Qingdao 266071, China