Department of Physics of Science and Data Analytics Teknologi Sepuluh Nopember;
Department of Electrical Engineering of Engineering of Muhammadiyah Malang;
Geopolymer&Green Technology Centre of Excellence Malaysia Perlis;
Applied Electromagnetic Laboratory 1 of Physics of Science Putra Malaysia;
Synchrotron Light Research Institute(SLRI) Ratchasima;
N-DOPED; rGO−like carbon; coconut shell; specific capacitance;