[1] Padjadjaran State Univ, Nanotechnol & Graphene Res Ctr, Jl Raya Bandung Sumedang KM 21, Jatinangor 45363, West Java, Indonesia
[2] Anna Univ, Dept Chem Engn, AC Tech Campus, Madras, Tamil Nadu, India
[3] Padjadjaran State Univ, Fac Math & Nat Sci, Dept Phys, Jl Raya Bandung Sumedang KM 21, Jatinangor 45363, West Java, Indonesia