[1] Nanyang Technol Univ, Sch Phys & Math Sci, Div Phys & Appl Phys, Singapore 637371, Singapore
[2] Tsinghua Univ, Tsinghua Berkeley Shenzhen Inst, Shenzhen 518055, Guangdong, Peoples R China
[3] Tsinghua Univ, Shenzhen Geim Graphene Ctr, Shenzhen 518055, Guangdong, Peoples R China
[4] ASTAR, Inst Mat Res & Engn IMRE, Singapore 138634, Singapore
[5] Chinese Acad Sci, Key Lab Magnet Mat & Devices, Ningbo Inst Mat Technol & Engn, Ningbo 315201, Peoples R China
[6] Nanyang Technol Univ, Sch Elect & Elect Engn, Singapore 639798, Singapore
[7] ASTAR, Energy & Environm ISCE2, Inst Sustainabil Chem, Singapore 627833, Singapore
[8] Nanyang Technol Univ, Sch Chem Chem Engn & Biotechnol, Singapore 637371, Singapore
[9] Tsinghua Shenzhen Int Grad Sch, Inst Mat Res, Guangdong Prov Key Lab Thermal Management Engn &, Shenzhen 518055, Guangdong, Peoples R China