High performance in the removal of methylene blue dye by photocatalyst absorbent activity of green synthesis CuO@NiO/geopolymer composites

High-performance composites for the removal of organic methylene blue (MB) dye, specifically bimetallic nanocluster particles CuO@NiO fabricated on geopolymer, have been successfully developed from swollen finger grass extract solution by a simultaneous reduction process incorporated into biomass ash geopolymer materials. Using an ultraviolet-visible (UV-Vis) spectrometer, we observe that the CuO@NiO/geopolymer composites with 10 wt% exhibit superior catalytic absorbent activity in absorbing MB dye compared to pure biomass ash geopolymer and other metal oxides incorporated with geopolymer materials. We attribute this enhanced ability to the simultaneous processes of photodegradation and adsorption. This work demonstrates a new concept in the development of low-cost and eco-friendly materials with high efficiency for removing organic MB dye, applicable in wastewater treatments.