[1] Indian Inst Technol Madras IITM, Dept Chem, DST Unit Nanosci DST UNS, Chennai 600036, India
[2] Indian Inst Technol Madras IITM, Dept Chem, Themat Unit Excellence TUE, Chennai 600036, India
[3] Univ Texas Austin, Dept Chem, Austin, TX 45355 USA
[4] Univ Jyvaskyla, Nanosci Ctr, Dept Chem & Phys, FI-40014 Jyvaskyla, Finland
[5] Int Ctr Clean Water, 2nd Floor,B Block,IIT Madras Res Pk,Kanagam Rd, Chennai 600113, India