Optimization of Calcination Temperature to Synthesis ZnO Nanostructures as Photocatalyst Using Pineapple as Chelating Agent

Abstract ZnO nanostructures were successfully synthesized using the sol-gel method with pineapple extract ( Ananas comosus (L.) ) as a chelating agent. ZnO nanostructures using cayenne pineapple ( Ananas comosus var.cayenne ) chelate were calcined at temperatures ranging from 500 ˚C to 900 ˚C, while queen pineapple ( Ananas comosus var.queen ) was calcined at 700 ˚C and 800 ˚C. ZnO nanostructures synthesized with cayenne pineapple chelate and calcinated at 800 ˚C showed an average particle size of 1.858 μm and an average crystallite size of 35.10 nm, while at 700 ˚C, it was 30.90 nm. The diffraction peaks can be indexed as a hexagonal wurtzite structure (a = 3.25x10 −10 m, c = 5.21x10 −10 m). The photocatalytic activity of ZnO was evaluated for the photodegradation of methylene blue under UV light radiation. The most effective degradation was achieved with ZnO nanostructures synthesized with cayenne pineapple chelate at a calcination temperature of 700 ˚C under UV light irradiation for 240 minutes. The degradation rate was 55.87% at a concentration of 10 ppm MB solution.