Adsorption of methylene blue using Fe₃O₄/CuO/ZnO/ nanographene platelets (NGP) composites with various NGP concentration

This study will examine the use of Fe₃O₄/CuO/ZnO nanocomposites that have been modified by Nanographene Platelets (NGP) as an adsorbent to degrade organic dye waste Methylene Blue (MB). The nanocomposites were synthesized using the sol-gel method then combined with three variatons of NGP weight percents by simple hydrothermal method. The Fe₃O₄/CuO/ZnO/NGP composites were characterized using the X-Ray Diffraction (XRD) spectroscopy, Fourier Transform Infrared (FTIR), Energy Dispersive X-Ray (EDX), Thermogravimetric Analysis (TGA) and Vibrating Sample Magnetometer (VSM). The composites exhibit ferromagnetic behaviour. The presence of hexagonal wurtzite of ZnO, monoclinic of CuO and cubic spinel of Fe₃O₄ were found in the composites. The graphitic-like structure represents the presence of the NGP in the composites. However, the addition of NGP weight percent reduces the thermal stability of the composites. The adsorption capability of the composites are analyzed by observing the degradation of organic dye Methylene Blue (MB) under dark condition. The NGP addition of 15 wt% show the best result of the composites to degrade Methylene Blue in alkaline condition. Adsorption mechanism of the composites with NGP addition tend to follow the model Langmuir adsorption kinetic models.