[1] Chinese Acad Sci, Mat Interfaces Ctr, Shenzhen Inst Adv Technol, Shenzhen 518055, Peoples R China
[2] City Univ Hong Kong, Dept Mat Sci & Engn, Dept Phys, Kowloon, Tat Chee Ave, Hong Kong 999077, Peoples R China
[3] City Univ Hong Kong, Dept Biomed Engn, Kowloon, Tat Chee Ave, Hong Kong 999077, Peoples R China
[4] Tsinghua Univ, Shenzhen Geim Graphene Ctr, Tsinghua Berkeley Shenzhen Inst, Shenzhen 518055, Peoples R China
[5] Tsinghua Univ, Tsinghua Shenzhen Int Grad Sch, Shenzhen 518055, Peoples R China