[1] Univ Sari Mutiara Indonesia, Fac Sci Technol & Informat, Dept Chem, Jalan Kapten Muslim 79, Medan 20124, Indonesia
[2] Univ Sumatera Utara, Cellulos & Funct Mat Res Ctr, Jalan Bioteknol 1, Medan 20155, Indonesia
[3] Univ Sumatera Utara, Fac Math & Nat Sci, Dept Chem, Jalan Bioteknol 1, Medan 20155, Indonesia
[4] Univ Gadjah Mada, Fac Math & Nat Sci, Dept Chem, Yogyakarta 55281, Indonesia
[5] Nanyang Technol Univ, Sch Mat Sci & Engn, 50 Nanyang Ave,Block N4 1, Singapore 637335, Singapore